3,4-Lutidinium salts with the di­iodido­aurate(I) anion: structure of [(3,4-lut)₂H]⁺·[AuI₂]⁻ and of two polymorphs of [(3,4-lut)₂H⁺]₂·[AuI₂]⁻·I⁻

Reactions between potassium tetra­iodido­aurate(III) and pyridine (py, C₅H₅N) or 3,4-luti­dine (3,4-di­methyl­pyridine, 3,4-lut, C₇H₉N) were tested as possible sources of aza­aromatic complexes of gold(III) iodide, but all identifiable products con­tained gold(I). The previously known structure di­pyridine­gold(I) di­iodido­aurate(I), [Au(py)₂]⁺·[AuI₂]⁻, (3) [Adams et al. (1982). Z. Anorg. Allg. Chem. 485, 81–91], was redetermined at 100 K. The reactions with 3,4-lutidine gave three different types of crystal in small qu­anti­ties. 3,4-Di­methyl­pyridine–3,4-di­methyl­pyridinium di­iodido­aur­ate(I), [(3,4-lut)₂H]⁺·[AuI₂]⁻, (1), consists of an [AuI₂]⁻ anion on a general position and two [(3,4-lut)₂H]⁺ cations across two­fold axes. Bis(3,4-di­methyl­pyridine–3,4-di­methyl­pyridinium) di­iodido­aur­ate(I) iodide, [(3,4-lut)₂H⁺]₂·[AuI₂]⁻·I⁻, (2), crystallizes as two polymorphs, each forming pseudosymmetric inversion twins, in the space groups P2₁ and Pc (but resembling P2₁/m and P2/c), respectively. These are essentially identical layer structures differing only in their stacking patterns and thus might be regarded as polytypes.

Computing details

For all structures, data collection: CrysAlis PRO (Rigaku OD, 2015); cell refinement: CrysAlis PRO (Rigaku OD, 2015); data reduction: CrysAlis PRO (Rigaku OD, 2015). Program(s) used to solve structure: SHELXL97 (Sheldrick, 2008) for (1); SHELXS97 (Sheldrick, 2008) for (2a), (2b), (3). Program(s) used to refine structure: SHELXL2017 (Sheldrick, 2015) for (1); SHELXL2014 (Sheldrick, 2015) for (2a), (2b), (3). For all structures, molecular graphics: XP (Siemens, 1994). Software used to prepare material for publication: SHELXL2017 (Sheldrick, 2015) for (1); SHELXL2014 (Sheldrick, 2015) for (2a), (2b), (3).

3,4-Dimethylpyridine–3,4-dimethylpyridinium diiodidoaurate(I) (1)

Crystal data

(C14H19N2)[AuI2]	F(000) = 1208
Mr = 666.08	Dx = 2.505 Mg m^−3
Monoclinic, P2/c	Mo Kα radiation, λ = 0.71073 Å
a = 15.5270 (5) Å	Cell parameters from 24363 reflections
b = 7.46802 (1) Å	θ = 2.7–30.8°
c = 17.0254 (5) Å	µ = 11.82 mm^−1
β = 116.528 (4)°	T = 105 K
V = 1766.34 (10) Å^3	Block, orange
Z = 4	0.10 × 0.10 × 0.07 mm

Data collection

Oxford Diffraction Xcalibur Eos diffractometer	5434 independent reflections
Radiation source: fine-focus sealed X-ray tube	4885 reflections with I > 2σ(I)
Detector resolution: 16.1419 pixels mm^-1	Rint = 0.048
ω–scan	θmax = 31.1°, θmin = 2.4°
Absorption correction: multi-scan (CrysAlis PRO; Rigaku OD, 2015)	h = −22→21
Tmin = 0.558, Tmax = 1.000	k = −10→10
90918 measured reflections	l = −24→24

Refinement

Refinement on F^2	9 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F^2 > 2σ(F^2)] = 0.021	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.041	w = 1/[σ^2(Fo^2) + (0.0148P)^2 + 1.8741P] where P = (Fo^2 + 2Fc^2)/3
S = 1.10	(Δ/σ)max = 0.002
5434 reflections	Δρmax = 1.07 e Å^−3
182 parameters	Δρmin = −1.18 e Å^−3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
Au1	0.25903 (2)	0.93379 (2)	0.31445 (2)	0.01825 (3)
I1	0.16641 (2)	0.97466 (2)	0.40452 (2)	0.02499 (5)
I2	0.35148 (2)	0.88824 (2)	0.22507 (2)	0.02128 (4)
N11	0.04319 (17)	0.4279 (3)	0.19872 (15)	0.0204 (5)
H01	0.015 (3)	0.416 (3)	0.232 (3)	0.024*	0.5
C12	0.0387 (2)	0.5861 (4)	0.15969 (19)	0.0221 (6)
H12	0.002830	0.680136	0.168608	0.027*
C13	0.08380 (19)	0.6187 (4)	0.10718 (18)	0.0195 (5)
C14	0.1379 (2)	0.4800 (4)	0.09541 (18)	0.0207 (6)
C15	0.1415 (2)	0.3167 (4)	0.13683 (19)	0.0234 (6)
H15	0.177434	0.220090	0.129972	0.028*
C16	0.0940 (2)	0.2943 (4)	0.18713 (18)	0.0230 (6)
H16	0.097097	0.181916	0.214387	0.028*
C17	0.0743 (2)	0.7986 (4)	0.0648 (2)	0.0294 (7)
H17A	0.034264	0.876641	0.081213	0.044*
H17B	0.044323	0.784461	0.000853	0.044*
H17C	0.138292	0.852215	0.084659	0.044*
C18	0.1904 (2)	0.5068 (5)	0.0414 (2)	0.0323 (7)
H18A	0.240198	0.598378	0.068794	0.048*
H18B	0.145081	0.545740	−0.017685	0.048*
H18C	0.220557	0.393900	0.037688	0.048*
N21	0.51421 (17)	0.6874 (3)	0.67913 (15)	0.0189 (5)
H02	0.503 (2)	0.685 (5)	0.724 (2)	0.023*	0.5
C22	0.5943 (2)	0.6129 (3)	0.68240 (18)	0.0190 (5)
H22	0.636015	0.551261	0.734393	0.023*
C23	0.61934 (19)	0.6209 (3)	0.61465 (17)	0.0154 (5)
C24	0.55649 (18)	0.7109 (3)	0.53747 (17)	0.0154 (5)
C25	0.47362 (19)	0.7874 (3)	0.53512 (18)	0.0179 (5)
H25	0.429858	0.848738	0.483912	0.022*
C26	0.4547 (2)	0.7746 (3)	0.60676 (18)	0.0196 (5)
H26	0.398293	0.828794	0.604509	0.023*
C27	0.7107 (2)	0.5362 (4)	0.62314 (19)	0.0203 (5)
H27A	0.744391	0.480406	0.681127	0.031*
H27B	0.751906	0.627943	0.616294	0.031*
H27C	0.695350	0.444721	0.577551	0.031*
C28	0.5793 (2)	0.7264 (4)	0.46125 (17)	0.0200 (5)
H28A	0.638341	0.796680	0.478534	0.030*
H28B	0.526015	0.786188	0.412443	0.030*
H28C	0.588608	0.606633	0.442803	0.030*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Au1	0.01953 (5)	0.01514 (5)	0.01951 (6)	−0.00032 (4)	0.00822 (4)	0.00105 (4)
I1	0.02956 (10)	0.02067 (9)	0.03144 (10)	−0.00359 (7)	0.01963 (9)	−0.00095 (7)
I2	0.02285 (9)	0.02021 (9)	0.02230 (9)	−0.00231 (6)	0.01143 (7)	−0.00114 (7)
N11	0.0207 (12)	0.0216 (12)	0.0205 (12)	0.0007 (9)	0.0107 (10)	0.0032 (9)
C12	0.0186 (13)	0.0210 (13)	0.0261 (15)	0.0027 (10)	0.0094 (12)	0.0017 (11)
C13	0.0161 (13)	0.0218 (13)	0.0165 (13)	−0.0010 (10)	0.0035 (10)	0.0024 (10)
C14	0.0180 (13)	0.0266 (14)	0.0155 (13)	−0.0051 (10)	0.0055 (11)	−0.0064 (10)
C15	0.0242 (14)	0.0208 (13)	0.0254 (15)	−0.0011 (11)	0.0112 (12)	−0.0055 (11)
C16	0.0248 (14)	0.0216 (13)	0.0199 (14)	0.0005 (11)	0.0077 (12)	0.0025 (11)
C17	0.0267 (15)	0.0260 (15)	0.0335 (17)	−0.0017 (12)	0.0118 (14)	0.0099 (13)
C18	0.0376 (18)	0.0348 (17)	0.0326 (18)	−0.0111 (14)	0.0229 (15)	−0.0106 (14)
N21	0.0274 (12)	0.0163 (10)	0.0171 (11)	−0.0031 (9)	0.0137 (10)	−0.0019 (8)
C22	0.0254 (14)	0.0124 (11)	0.0184 (13)	−0.0028 (10)	0.0090 (11)	−0.0009 (9)
C23	0.0179 (12)	0.0108 (11)	0.0176 (12)	−0.0031 (9)	0.0080 (10)	−0.0016 (9)
C24	0.0182 (12)	0.0113 (11)	0.0165 (12)	−0.0044 (9)	0.0076 (10)	−0.0029 (9)
C25	0.0199 (13)	0.0136 (12)	0.0197 (13)	−0.0001 (9)	0.0082 (11)	0.0005 (10)
C26	0.0206 (13)	0.0152 (12)	0.0246 (14)	−0.0019 (10)	0.0115 (11)	−0.0030 (10)
C27	0.0201 (13)	0.0172 (12)	0.0236 (14)	0.0013 (10)	0.0097 (11)	0.0008 (10)
C28	0.0236 (14)	0.0208 (13)	0.0178 (13)	−0.0017 (10)	0.0111 (11)	−0.0002 (10)

Geometric parameters (Å, º)

Au1—I2	2.5385 (2)	C18—H18C	0.9800
Au1—I1	2.5460 (2)	N21—C26	1.334 (4)
N11—C16	1.340 (4)	N21—C22	1.341 (4)
N11—C12	1.342 (4)	N21—H02	0.86 (4)
N11—H01	0.86 (4)	C22—C23	1.373 (4)
C12—C13	1.381 (4)	C22—H22	0.9500
C12—H12	0.9500	C23—C24	1.409 (4)
C13—C14	1.403 (4)	C23—C27	1.500 (4)
C13—C17	1.501 (4)	C24—C25	1.392 (4)
C14—C15	1.397 (4)	C24—C28	1.495 (4)
C14—C18	1.490 (4)	C25—C26	1.380 (4)
C15—C16	1.368 (4)	C25—H25	0.9500
C15—H15	0.9500	C26—H26	0.9500
C16—H16	0.9500	C27—H27A	0.9800
C17—H17A	0.9800	C27—H27B	0.9800
C17—H17B	0.9800	C27—H27C	0.9800
C17—H17C	0.9800	C28—H28A	0.9800
C18—H18A	0.9800	C28—H28B	0.9800
C18—H18B	0.9800	C28—H28C	0.9800
I2—Au1—I1	179.176 (7)	C26—N21—C22	119.2 (2)
C16—N11—C12	119.1 (2)	C26—N21—H02	120.4 (12)
C16—N11—H01	121.7 (11)	C22—N21—H02	120.3 (12)
C12—N11—H01	119.2 (11)	N21—C22—C23	123.5 (3)
N11—C12—C13	123.1 (3)	N21—C22—H22	118.2
N11—C12—H12	118.4	C23—C22—H22	118.2
C13—C12—H12	118.4	C22—C23—C24	117.8 (2)
C12—C13—C14	118.1 (3)	C22—C23—C27	120.7 (2)
C12—C13—C17	120.0 (3)	C24—C23—C27	121.5 (2)
C14—C13—C17	121.9 (3)	C25—C24—C23	118.0 (2)
C15—C14—C13	117.6 (3)	C25—C24—C28	121.2 (2)
C15—C14—C18	121.2 (3)	C23—C24—C28	120.8 (2)
C13—C14—C18	121.1 (3)	C26—C25—C24	120.3 (2)
C16—C15—C14	120.7 (3)	C26—C25—H25	119.8
C16—C15—H15	119.6	C24—C25—H25	119.8
C14—C15—H15	119.6	N21—C26—C25	121.2 (3)
N11—C16—C15	121.3 (3)	N21—C26—H26	119.4
N11—C16—H16	119.4	C25—C26—H26	119.4
C15—C16—H16	119.4	C23—C27—H27A	109.5
C13—C17—H17A	109.5	C23—C27—H27B	109.5
C13—C17—H17B	109.5	H27A—C27—H27B	109.5
H17A—C17—H17B	109.5	C23—C27—H27C	109.5
C13—C17—H17C	109.5	H27A—C27—H27C	109.5
H17A—C17—H17C	109.5	H27B—C27—H27C	109.5
H17B—C17—H17C	109.5	C24—C28—H28A	109.5
C14—C18—H18A	109.5	C24—C28—H28B	109.5
C14—C18—H18B	109.5	H28A—C28—H28B	109.5
H18A—C18—H18B	109.5	C24—C28—H28C	109.5
C14—C18—H18C	109.5	H28A—C28—H28C	109.5
H18A—C18—H18C	109.5	H28B—C28—H28C	109.5
H18B—C18—H18C	109.5
C16—N11—C12—C13	0.4 (4)	C26—N21—C22—C23	0.0 (4)
N11—C12—C13—C14	−1.0 (4)	N21—C22—C23—C24	−0.7 (4)
N11—C12—C13—C17	179.2 (3)	N21—C22—C23—C27	179.3 (2)
C12—C13—C14—C15	0.8 (4)	C22—C23—C24—C25	0.6 (4)
C17—C13—C14—C15	−179.3 (3)	C27—C23—C24—C25	−179.4 (2)
C12—C13—C14—C18	−178.5 (3)	C22—C23—C24—C28	179.5 (2)
C17—C13—C14—C18	1.3 (4)	C27—C23—C24—C28	−0.5 (4)
C13—C14—C15—C16	−0.2 (4)	C23—C24—C25—C26	0.1 (4)
C18—C14—C15—C16	179.2 (3)	C28—C24—C25—C26	−178.8 (2)
C12—N11—C16—C15	0.3 (4)	C22—N21—C26—C25	0.8 (4)
C14—C15—C16—N11	−0.4 (4)	C24—C25—C26—N21	−0.8 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N11—H01···N11^i	0.86 (4)	1.78 (4)	2.634 (5)	171 (2)
N21—H02···N21^ii	0.86 (4)	1.78 (4)	2.640 (4)	177 (4)
C12—H12···I1^i	0.95	3.22	4.080 (3)	152
C16—H16···I1^iii	0.95	3.30	4.116 (3)	145
C17—H17C···I2	0.98	3.11	3.990 (3)	150
C18—H18A···I2	0.98	3.26	4.142 (3)	150
C26—H26···I2^iv	0.95	3.25	3.981 (3)	136
C28—H28B···I2	0.98	3.22	4.176 (3)	165
C16—H16···Au1^iii	0.95	2.97	3.681 (3)	133
C25—H25···Au1	0.95	2.99	3.903 (3)	162
C27—H27A···Au1^v	0.98	3.10	3.636 (3)	116

Symmetry codes: (i) −x, y, −z+1/2; (ii) −x+1, y, −z+3/2; (iii) x, y−1, z; (iv) x, −y+2, z+1/2; (v) −x+1, −y+1, −z+1.

Bis(3,4-dimethylpyridine–3,4-dimethylpyridinium) diiodidoaurate(I) iodide (2a)

Crystal data

(C14H19N2)2[AuI2]I	F(000) = 944
Mr = 1008.29	Dx = 2.093 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
a = 7.7528 (2) Å	Cell parameters from 19240 reflections
b = 14.5978 (5) Å	θ = 2.7–30.7°
c = 14.4806 (4) Å	µ = 7.52 mm^−1
β = 102.552 (3)°	T = 100 K
V = 1599.65 (8) Å^3	Block, colourless
Z = 2	0.25 × 0.10 × 0.04 mm

Data collection

Oxford Diffraction Xcalibur Eos diffractometer	9602 independent reflections
Radiation source: fine-focus sealed X-ray tube	8806 reflections with I > 2σ(I)
Detector resolution: 16.1419 pixels mm^-1	Rint = 0.055
ω scan	θmax = 31.1°, θmin = 2.7°
Absorption correction: multi-scan (CrysAlis PRO; Rigaku OD, 2015)	h = −11→11
Tmin = 0.546, Tmax = 1.000	k = −20→21
86977 measured reflections	l = −20→20

Refinement

Refinement on F^2	Hydrogen site location: mixed
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F^2 > 2σ(F^2)] = 0.027	w = 1/[σ^2(Fo^2) + (0.0163P)^2 + 1.8411P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.048	(Δ/σ)max = 0.001
S = 1.03	Δρmax = 0.93 e Å^−3
9602 reflections	Δρmin = −1.07 e Å^−3
340 parameters	Absolute structure: Refined as an inversion twin.
2 restraints	Absolute structure parameter: 0.400 (5)

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. Refined as a 2-component inversion twin. The NH hydrogens were refined freely, but with fixed U values. The N-H distances were refined using the SADI command.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Au1	−0.08775 (3)	0.25392 (2)	0.28981 (2)	0.01814 (5)
I1	−0.05892 (5)	0.26878 (3)	0.46711 (2)	0.02156 (9)
I2	−0.10926 (5)	0.23401 (2)	0.11347 (3)	0.02075 (9)
I3	−0.10057 (4)	0.74907 (3)	0.23916 (2)	0.01663 (7)
N11	0.5106 (7)	0.6695 (3)	0.3811 (4)	0.0173 (11)
H01	0.522 (8)	0.726 (3)	0.373 (4)	0.021*
C12	0.3438 (9)	0.6363 (4)	0.3717 (5)	0.0168 (12)
H12	0.2474	0.6779	0.3629	0.020*
C13	0.3119 (8)	0.5445 (4)	0.3746 (4)	0.0144 (12)
C14	0.4559 (8)	0.4842 (4)	0.3883 (4)	0.0171 (12)
C15	0.6256 (8)	0.5210 (4)	0.4000 (4)	0.0161 (12)
H15	0.7252	0.4814	0.4109	0.019*
C16	0.6493 (8)	0.6136 (4)	0.3959 (4)	0.0171 (12)
H16	0.7652	0.6380	0.4036	0.021*
C17	0.1250 (9)	0.5105 (5)	0.3649 (5)	0.0227 (14)
H17A	0.0427	0.5620	0.3492	0.034*
H17B	0.1121	0.4830	0.4248	0.034*
H17C	0.0988	0.4645	0.3145	0.034*
C18	0.4269 (9)	0.3826 (4)	0.3881 (5)	0.0228 (14)
H18A	0.3633	0.3632	0.3251	0.034*
H18B	0.3571	0.3670	0.4348	0.034*
H18C	0.5413	0.3513	0.4043	0.034*
N21	0.5053 (7)	0.8572 (3)	0.3660 (4)	0.0178 (11)
C22	0.3418 (8)	0.8922 (4)	0.3546 (4)	0.0158 (12)
H22	0.2462	0.8505	0.3498	0.019*
C23	0.3030 (8)	0.9850 (4)	0.3494 (4)	0.0155 (12)
C24	0.4433 (8)	1.0468 (4)	0.3569 (4)	0.0153 (11)
C25	0.6139 (9)	1.0112 (4)	0.3685 (5)	0.0187 (13)
H25	0.7121	1.0512	0.3737	0.022*
C26	0.6390 (8)	0.9168 (4)	0.3723 (5)	0.0189 (13)
H26	0.7557	0.8937	0.3797	0.023*
C27	0.1144 (8)	1.0162 (4)	0.3371 (5)	0.0233 (15)
H27A	0.0361	0.9627	0.3277	0.035*
H27B	0.0840	1.0564	0.2818	0.035*
H27C	0.1003	1.0496	0.3936	0.035*
C28	0.4134 (9)	1.1483 (4)	0.3518 (5)	0.0250 (14)
H28A	0.3604	1.1677	0.4042	0.038*
H28B	0.3337	1.1638	0.2915	0.038*
H28C	0.5266	1.1798	0.3563	0.038*
N31	0.2902 (7)	0.8332 (3)	0.1217 (4)	0.0167 (11)
H02	0.282 (8)	0.777 (3)	0.128 (4)	0.020*
C32	0.4550 (8)	0.8656 (4)	0.1297 (4)	0.0171 (12)
H32	0.5519	0.8243	0.1442	0.020*
C33	0.4868 (8)	0.9567 (4)	0.1175 (4)	0.0160 (12)
C34	0.3426 (8)	1.0168 (4)	0.0961 (4)	0.0180 (12)
C35	0.1724 (8)	0.9803 (4)	0.0886 (4)	0.0188 (12)
H35	0.0726	1.0197	0.0746	0.023*
C36	0.1490 (8)	0.8884 (4)	0.1014 (4)	0.0187 (12)
H36	0.0335	0.8642	0.0959	0.022*
C37	0.6729 (8)	0.9905 (4)	0.1281 (5)	0.0217 (14)
H37A	0.7551	0.9390	0.1442	0.032*
H37B	0.6982	1.0364	0.1786	0.032*
H37C	0.6870	1.0181	0.0685	0.032*
C38	0.3669 (9)	1.1165 (4)	0.0803 (5)	0.0242 (14)
H38A	0.2521	1.1474	0.0698	0.036*
H38B	0.4183	1.1247	0.0247	0.036*
H38C	0.4462	1.1427	0.1360	0.036*
N41	0.2987 (7)	0.6421 (3)	0.1351 (4)	0.0162 (10)
C42	0.4627 (8)	0.6074 (4)	0.1483 (4)	0.0161 (12)
H42	0.5586	0.6494	0.1600	0.019*
C43	0.5027 (8)	0.5150 (4)	0.1460 (4)	0.0163 (12)
C44	0.3611 (8)	0.4529 (4)	0.1298 (4)	0.0172 (12)
C45	0.1914 (8)	0.4886 (4)	0.1181 (4)	0.0191 (12)
H45	0.0926	0.4484	0.1084	0.023*
C46	0.1659 (8)	0.5819 (4)	0.1205 (4)	0.0172 (12)
H46	0.0484	0.6045	0.1114	0.021*
C47	0.6914 (8)	0.4838 (4)	0.1627 (5)	0.0228 (14)
H47A	0.7699	0.5368	0.1779	0.034*
H47B	0.7122	0.4538	0.1056	0.034*
H47C	0.7151	0.4404	0.2156	0.034*
C48	0.3916 (9)	0.3520 (4)	0.1237 (5)	0.0278 (15)
H48A	0.4807	0.3323	0.1790	0.042*
H48B	0.4333	0.3385	0.0660	0.042*
H48C	0.2808	0.3192	0.1222	0.042*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Au1	0.01646 (9)	0.01710 (9)	0.02050 (10)	0.00138 (8)	0.00323 (7)	0.00172 (9)
I1	0.01955 (16)	0.0248 (2)	0.01993 (17)	0.00141 (15)	0.00345 (13)	0.00165 (15)
I2	0.02184 (17)	0.0195 (2)	0.02131 (18)	−0.00001 (14)	0.00560 (14)	0.00055 (14)
I3	0.01131 (13)	0.01514 (17)	0.02316 (15)	0.00036 (14)	0.00314 (11)	0.00118 (15)
N11	0.019 (3)	0.014 (2)	0.018 (3)	0.0007 (19)	0.003 (2)	0.000 (2)
C12	0.016 (3)	0.015 (3)	0.019 (3)	0.004 (2)	0.004 (2)	0.002 (2)
C13	0.016 (3)	0.016 (3)	0.011 (3)	0.000 (2)	0.002 (2)	0.001 (2)
C14	0.023 (3)	0.017 (3)	0.010 (3)	0.002 (2)	0.001 (2)	0.001 (2)
C15	0.015 (3)	0.018 (3)	0.017 (3)	0.004 (2)	0.005 (2)	−0.002 (2)
C16	0.015 (3)	0.021 (3)	0.014 (3)	0.001 (2)	0.001 (2)	0.000 (2)
C17	0.018 (3)	0.022 (3)	0.027 (4)	−0.001 (2)	0.004 (3)	0.004 (3)
C18	0.025 (3)	0.016 (3)	0.026 (4)	0.001 (2)	0.003 (3)	0.001 (3)
N21	0.018 (3)	0.014 (2)	0.021 (3)	0.0010 (19)	0.004 (2)	0.000 (2)
C22	0.013 (3)	0.018 (3)	0.016 (3)	−0.005 (2)	0.005 (2)	−0.002 (2)
C23	0.013 (3)	0.020 (3)	0.013 (3)	0.000 (2)	0.000 (2)	−0.003 (2)
C24	0.015 (3)	0.014 (3)	0.016 (3)	0.002 (2)	0.003 (2)	−0.001 (2)
C25	0.017 (3)	0.017 (3)	0.021 (3)	−0.004 (2)	0.003 (3)	0.000 (2)
C26	0.014 (3)	0.024 (3)	0.019 (3)	0.000 (2)	0.005 (2)	0.000 (2)
C27	0.013 (3)	0.024 (3)	0.033 (4)	0.001 (2)	0.004 (3)	−0.002 (3)
C28	0.025 (4)	0.014 (3)	0.036 (4)	−0.001 (2)	0.007 (3)	−0.004 (3)
N31	0.017 (3)	0.012 (2)	0.020 (3)	0.0012 (18)	0.001 (2)	0.0018 (19)
C32	0.018 (3)	0.018 (3)	0.016 (3)	0.002 (2)	0.004 (2)	−0.002 (2)
C33	0.016 (3)	0.016 (3)	0.015 (3)	−0.001 (2)	0.003 (2)	−0.001 (2)
C34	0.025 (3)	0.014 (3)	0.016 (3)	0.001 (2)	0.007 (3)	0.001 (2)
C35	0.017 (3)	0.020 (3)	0.019 (3)	0.004 (2)	0.005 (2)	0.003 (2)
C36	0.014 (3)	0.022 (3)	0.020 (3)	−0.005 (2)	0.003 (2)	−0.002 (2)
C37	0.017 (3)	0.021 (3)	0.027 (4)	−0.005 (2)	0.005 (3)	0.004 (3)
C38	0.026 (3)	0.011 (3)	0.038 (4)	0.003 (2)	0.012 (3)	0.003 (3)
N41	0.019 (3)	0.015 (2)	0.015 (3)	0.0021 (18)	0.003 (2)	0.0011 (19)
C42	0.015 (3)	0.016 (3)	0.017 (3)	−0.003 (2)	0.002 (2)	0.002 (2)
C43	0.014 (3)	0.022 (3)	0.013 (3)	0.001 (2)	0.001 (2)	0.000 (2)
C44	0.018 (3)	0.017 (3)	0.018 (3)	0.000 (2)	0.007 (2)	−0.002 (2)
C45	0.017 (3)	0.020 (3)	0.020 (3)	−0.003 (2)	0.005 (3)	−0.003 (2)
C46	0.012 (3)	0.020 (3)	0.019 (3)	0.000 (2)	0.001 (2)	−0.001 (2)
C47	0.014 (3)	0.021 (3)	0.033 (4)	0.004 (2)	0.004 (3)	0.002 (3)
C48	0.028 (4)	0.017 (3)	0.040 (4)	0.000 (3)	0.012 (3)	−0.004 (3)

Geometric parameters (Å, º)

Au1—I1	2.5375 (4)	C15—H15	0.9500
Au1—I2	2.5393 (4)	C16—H16	0.9500
N11—C16	1.330 (8)	C17—H17A	0.9800
N11—C12	1.360 (8)	C17—H17B	0.9800
C12—C13	1.365 (8)	C17—H17C	0.9800
C13—C14	1.401 (8)	C18—H18A	0.9800
C13—C17	1.509 (9)	C18—H18B	0.9800
C14—C15	1.396 (9)	C18—H18C	0.9800
C14—C18	1.500 (9)	C22—H22	0.9500
C15—C16	1.367 (8)	C25—H25	0.9500
N21—C26	1.341 (8)	C26—H26	0.9500
N21—C22	1.344 (8)	C27—H27A	0.9800
C22—C23	1.386 (8)	C27—H27B	0.9800
C23—C24	1.398 (9)	C27—H27C	0.9800
C23—C27	1.504 (9)	C28—H28A	0.9800
C24—C25	1.396 (9)	C28—H28B	0.9800
C24—C28	1.500 (8)	C28—H28C	0.9800
C25—C26	1.390 (8)	N31—H02	0.83 (5)
N31—C36	1.340 (8)	C32—H32	0.9500
N31—C32	1.343 (8)	C35—H35	0.9500
C32—C33	1.371 (8)	C36—H36	0.9500
C33—C34	1.402 (8)	C37—H37A	0.9800
C33—C37	1.501 (8)	C37—H37B	0.9800
C34—C35	1.405 (9)	C37—H37C	0.9800
C34—C38	1.491 (8)	C38—H38A	0.9800
C35—C36	1.371 (8)	C38—H38B	0.9800
N41—C46	1.335 (7)	C38—H38C	0.9800
N41—C42	1.343 (8)	C42—H42	0.9500
C42—C43	1.387 (8)	C45—H45	0.9500
C43—C44	1.403 (8)	C46—H46	0.9500
C43—C47	1.501 (9)	C47—H47A	0.9800
C44—C45	1.391 (8)	C47—H47B	0.9800
C44—C48	1.497 (8)	C47—H47C	0.9800
C45—C46	1.378 (8)	C48—H48A	0.9800
N11—H01	0.84 (5)	C48—H48B	0.9800
C12—H12	0.9500	C48—H48C	0.9800
I1—Au1—I2	177.920 (17)	H18A—C18—H18C	109.5
C16—N11—C12	121.0 (5)	H18B—C18—H18C	109.5
N11—C12—C13	121.5 (6)	N21—C22—H22	117.7
C12—C13—C14	118.5 (6)	C23—C22—H22	117.7
C12—C13—C17	119.8 (6)	C26—C25—H25	120.2
C14—C13—C17	121.8 (5)	C24—C25—H25	120.2
C15—C14—C13	118.4 (6)	N21—C26—H26	118.6
C15—C14—C18	121.2 (5)	C25—C26—H26	118.6
C13—C14—C18	120.4 (6)	C23—C27—H27A	109.5
C16—C15—C14	120.5 (6)	C23—C27—H27B	109.5
N11—C16—C15	120.1 (6)	H27A—C27—H27B	109.5
C26—N21—C22	117.1 (5)	C23—C27—H27C	109.5
N21—C22—C23	124.5 (5)	H27A—C27—H27C	109.5
C22—C23—C24	118.0 (6)	H27B—C27—H27C	109.5
C22—C23—C27	119.7 (5)	C24—C28—H28A	109.5
C24—C23—C27	122.3 (5)	C24—C28—H28B	109.5
C25—C24—C23	118.0 (5)	H28A—C28—H28B	109.5
C25—C24—C28	120.4 (5)	C24—C28—H28C	109.5
C23—C24—C28	121.6 (5)	H28A—C28—H28C	109.5
C26—C25—C24	119.6 (6)	H28B—C28—H28C	109.5
N21—C26—C25	122.8 (6)	C36—N31—H02	123 (4)
C36—N31—C32	121.5 (5)	C32—N31—H02	116 (4)
N31—C32—C33	121.6 (5)	N31—C32—H32	119.2
C32—C33—C34	118.6 (6)	C33—C32—H32	119.2
C32—C33—C37	120.1 (5)	C36—C35—H35	119.7
C34—C33—C37	121.3 (5)	C34—C35—H35	119.7
C33—C34—C35	118.1 (5)	N31—C36—H36	120.2
C33—C34—C38	121.6 (6)	C35—C36—H36	120.2
C35—C34—C38	120.4 (6)	C33—C37—H37A	109.5
C36—C35—C34	120.6 (6)	C33—C37—H37B	109.5
N31—C36—C35	119.5 (6)	H37A—C37—H37B	109.5
C46—N41—C42	116.7 (5)	C33—C37—H37C	109.5
N41—C42—C43	124.9 (5)	H37A—C37—H37C	109.5
C42—C43—C44	117.5 (5)	H37B—C37—H37C	109.5
C42—C43—C47	120.4 (5)	C34—C38—H38A	109.5
C44—C43—C47	122.1 (6)	C34—C38—H38B	109.5
C45—C44—C43	117.6 (5)	H38A—C38—H38B	109.5
C45—C44—C48	121.2 (6)	C34—C38—H38C	109.5
C43—C44—C48	121.1 (6)	H38A—C38—H38C	109.5
C46—C45—C44	120.3 (5)	H38B—C38—H38C	109.5
N41—C46—C45	123.0 (5)	N41—C42—H42	117.5
C16—N11—H01	121 (4)	C43—C42—H42	117.5
C12—N11—H01	117 (4)	C46—C45—H45	119.9
N11—C12—H12	119.3	C44—C45—H45	119.9
C13—C12—H12	119.3	N41—C46—H46	118.5
C16—C15—H15	119.8	C45—C46—H46	118.5
C14—C15—H15	119.8	C43—C47—H47A	109.5
N11—C16—H16	119.9	C43—C47—H47B	109.5
C15—C16—H16	119.9	H47A—C47—H47B	109.5
C13—C17—H17A	109.5	C43—C47—H47C	109.5
C13—C17—H17B	109.5	H47A—C47—H47C	109.5
H17A—C17—H17B	109.5	H47B—C47—H47C	109.5
C13—C17—H17C	109.5	C44—C48—H48A	109.5
H17A—C17—H17C	109.5	C44—C48—H48B	109.5
H17B—C17—H17C	109.5	H48A—C48—H48B	109.5
C14—C18—H18A	109.5	C44—C48—H48C	109.5
C14—C18—H18B	109.5	H48A—C48—H48C	109.5
H18A—C18—H18B	109.5	H48B—C48—H48C	109.5
C14—C18—H18C	109.5
C16—N11—C12—C13	−1.7 (9)	C36—N31—C32—C33	0.0 (9)
N11—C12—C13—C14	0.5 (9)	N31—C32—C33—C34	0.0 (9)
N11—C12—C13—C17	179.3 (6)	N31—C32—C33—C37	179.3 (6)
C12—C13—C14—C15	1.1 (9)	C32—C33—C34—C35	0.2 (9)
C17—C13—C14—C15	−177.7 (6)	C37—C33—C34—C35	−179.1 (6)
C12—C13—C14—C18	−177.6 (5)	C32—C33—C34—C38	−179.0 (6)
C17—C13—C14—C18	3.7 (9)	C37—C33—C34—C38	1.7 (9)
C13—C14—C15—C16	−1.5 (9)	C33—C34—C35—C36	−0.4 (9)
C18—C14—C15—C16	177.1 (6)	C38—C34—C35—C36	178.8 (6)
C12—N11—C16—C15	1.3 (9)	C32—N31—C36—C35	−0.2 (9)
C14—C15—C16—N11	0.3 (9)	C34—C35—C36—N31	0.4 (9)
C26—N21—C22—C23	−0.3 (10)	C46—N41—C42—C43	1.2 (9)
N21—C22—C23—C24	−0.3 (9)	N41—C42—C43—C44	−0.8 (9)
N21—C22—C23—C27	−179.7 (6)	N41—C42—C43—C47	−179.3 (6)
C22—C23—C24—C25	0.5 (9)	C42—C43—C44—C45	−0.6 (9)
C27—C23—C24—C25	179.9 (6)	C47—C43—C44—C45	178.0 (6)
C22—C23—C24—C28	179.8 (6)	C42—C43—C44—C48	178.5 (6)
C27—C23—C24—C28	−0.8 (10)	C47—C43—C44—C48	−3.0 (10)
C23—C24—C25—C26	−0.1 (10)	C43—C44—C45—C46	1.4 (9)
C28—C24—C25—C26	−179.4 (6)	C48—C44—C45—C46	−177.7 (6)
C22—N21—C26—C25	0.7 (10)	C42—N41—C46—C45	−0.4 (9)
C24—C25—C26—N21	−0.5 (10)	C44—C45—C46—N41	−0.9 (10)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N11—H01···N21	0.84 (5)	1.92 (5)	2.748 (7)	168 (6)
N31—H02···N41	0.83 (5)	1.98 (5)	2.796 (7)	170 (6)
C12—H12···I3	0.95	3.08	3.923 (6)	149
C16—H16···I3^i	0.95	3.23	3.839 (6)	123
C17—H17A···I3	0.98	3.23	4.138 (7)	154
C22—H22···I3	0.95	3.18	4.053 (6)	154
C32—H32···I3^i	0.95	2.96	3.860 (6)	159
C36—H36···I3	0.95	3.02	3.680 (6)	127
C37—H37A···I3^i	0.98	3.19	4.106 (6)	157
C42—H42···I3^i	0.95	3.02	3.941 (6)	165
C46—H46···I3	0.95	3.18	3.836 (6)	127
C16—H16···I1^ii	0.95	3.24	4.052 (6)	145
C48—H48C···I2	0.98	3.25	4.221 (7)	173
C27—H27B···Au1^iii	0.98	3.19	3.809 (6)	123
C47—H47C···Au1^i	0.98	3.19	4.026 (6)	144

Symmetry codes: (i) x+1, y, z; (ii) −x+1, y+1/2, −z+1; (iii) x, y+1, z.

Bis(3,4-dimethylpyridine–3,4-dimethylpyridinium) diiodidoaurate(I) iodide (2b)

Crystal data

(C14H19N2)[AuI2]I	F(000) = 944
Mr = 1008.29	Dx = 2.104 Mg m^−3
Monoclinic, Pc	Mo Kα radiation, λ = 0.71073 Å
a = 7.7410 (2) Å	Cell parameters from 14161 reflections
b = 14.6209 (3) Å	θ = 2.6–28.8°
c = 14.0721 (6) Å	µ = 7.55 mm^−1
β = 92.155 (3)°	T = 100 K
V = 1591.55 (9) Å^3	Block, colourless
Z = 2	0.20 × 0.08 × 0.05 mm

Data collection

Oxford Difraction Xcalibur Eos diffractometer	7889 independent reflections
Radiation source: fine-focus sealed X-ray tube	7209 reflections with I > 2σ(I)
Detector resolution: 16.1419 pixels mm^-1	Rint = 0.062
ω–scan	θmax = 28.3°, θmin = 2.6°
Absorption correction: multi-scan (CrysAlis PRO; Rigaku OD, 2015)	h = −10→10
Tmin = 0.690, Tmax = 1.000	k = −19→19
79049 measured reflections	l = −18→18

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F^2 > 2σ(F^2)] = 0.036	w = 1/[σ^2(Fo^2) + (0.0217P)^2 + 12.4269P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.081	(Δ/σ)max = 0.001
S = 1.11	Δρmax = 2.06 e Å^−3
7889 reflections	Δρmin = −1.58 e Å^−3
334 parameters	Absolute structure: Refined as an inversion twin.
8 restraints	Absolute structure parameter: 0.490 (11)

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. Refined as a 2-component inversion twin.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Au1	−0.02023 (13)	0.22665 (4)	0.23813 (8)	0.02430 (10)
I1	−0.05469 (11)	0.21526 (5)	0.41690 (7)	0.0270 (2)
I2	0.01533 (10)	0.24151 (6)	0.05939 (7)	0.0268 (2)
I3	−0.0173 (2)	0.72410 (5)	0.23662 (12)	0.01706 (12)
N11	0.5412 (15)	0.8059 (6)	0.3648 (9)	0.018 (2)
H11	0.5601	0.7466	0.3628	0.022*
C12	0.3767 (18)	0.8376 (8)	0.3625 (9)	0.018 (3)
H12	0.2843	0.7948	0.3590	0.022*
C13	0.3389 (17)	0.9282 (10)	0.3648 (10)	0.017 (3)
C14	0.4791 (18)	0.9907 (9)	0.3738 (10)	0.018 (3)
C15	0.6490 (18)	0.9557 (10)	0.3760 (10)	0.021 (3)
H15	0.7451	0.9960	0.3814	0.025*
C16	0.6747 (18)	0.8635 (8)	0.3703 (10)	0.019 (3)
H16	0.7892	0.8402	0.3701	0.023*
C17	0.157 (2)	0.9619 (9)	0.3640 (12)	0.027 (3)
H17A	0.0773	0.9100	0.3558	0.040*
H17B	0.1375	1.0050	0.3113	0.040*
H17C	0.1354	0.9927	0.4243	0.040*
C18	0.450 (2)	1.0927 (9)	0.3740 (12)	0.025 (3)
H18A	0.3734	1.1088	0.4253	0.038*
H18B	0.3968	1.1115	0.3128	0.038*
H18C	0.5611	1.1241	0.3841	0.038*
N21	0.5427 (16)	0.6169 (7)	0.3549 (8)	0.019 (2)
C22	0.3838 (18)	0.5825 (9)	0.3418 (10)	0.017 (3)
H22	0.2911	0.6246	0.3326	0.021*
C23	0.3443 (19)	0.4901 (9)	0.3405 (10)	0.021 (3)
C24	0.4780 (17)	0.4275 (9)	0.3544 (10)	0.019 (3)
C25	0.6460 (17)	0.4630 (8)	0.3696 (10)	0.018 (3)
H25	0.7411	0.4229	0.3809	0.022*
C26	0.6714 (18)	0.5566 (8)	0.3679 (10)	0.018 (3)
H26	0.7860	0.5792	0.3765	0.021*
C27	0.1576 (19)	0.4600 (9)	0.3252 (11)	0.023 (3)
H27A	0.1220	0.4250	0.3805	0.034*
H27B	0.1468	0.4217	0.2682	0.034*
H27C	0.0835	0.5140	0.3170	0.034*
C28	0.447 (2)	0.3268 (8)	0.3550 (10)	0.026 (3)
H28A	0.3611	0.3110	0.3047	0.039*
H28B	0.4041	0.3085	0.4168	0.039*
H28C	0.5554	0.2946	0.3438	0.039*
N31	0.4190 (14)	0.6422 (6)	0.1057 (8)	0.015 (2)
H31	0.4015	0.7015	0.1099	0.018*
C32	0.5809 (18)	0.6100 (10)	0.1159 (11)	0.020 (3)
H32	0.6741	0.6517	0.1251	0.024*
C33	0.6144 (17)	0.5174 (9)	0.1132 (9)	0.018 (2)
C34	0.4775 (18)	0.4576 (8)	0.0991 (10)	0.017 (3)
C35	0.3103 (17)	0.4937 (9)	0.0860 (10)	0.017 (3)
H35	0.2148	0.4538	0.0749	0.020*
C36	0.2838 (17)	0.5871 (8)	0.0893 (9)	0.016 (3)
H36	0.1708	0.6118	0.0800	0.019*
C37	0.799 (2)	0.4839 (9)	0.1258 (12)	0.024 (3)
H37A	0.8747	0.5357	0.1420	0.036*
H37B	0.8347	0.4558	0.0665	0.036*
H37C	0.8060	0.4386	0.1771	0.036*
C38	0.5084 (19)	0.3578 (8)	0.0955 (10)	0.024 (3)
H38A	0.4030	0.3269	0.0717	0.035*
H38B	0.5397	0.3353	0.1595	0.035*
H38C	0.6027	0.3450	0.0529	0.035*
N41	0.4243 (15)	0.8302 (7)	0.1163 (9)	0.018 (2)
C42	0.5852 (18)	0.8649 (8)	0.1213 (10)	0.019 (3)
H42	0.6793	0.8231	0.1244	0.023*
C43	0.6230 (16)	0.9575 (9)	0.1222 (10)	0.015 (3)
C44	0.4849 (16)	1.0194 (8)	0.1198 (8)	0.013 (2)
C45	0.3215 (19)	0.9833 (8)	0.1173 (10)	0.016 (2)
H45	0.2252	1.0236	0.1164	0.019*
C46	0.2923 (18)	0.8901 (8)	0.1159 (11)	0.021 (3)
H46	0.1769	0.8678	0.1146	0.025*
C47	0.810 (2)	0.9875 (9)	0.1289 (12)	0.023 (3)
H47A	0.8848	0.9336	0.1344	0.035*
H47B	0.8291	1.0264	0.1850	0.035*
H47C	0.8373	1.0220	0.0716	0.035*
C48	0.520 (2)	1.1205 (9)	0.1207 (10)	0.022 (3)
H48A	0.4110	1.1540	0.1232	0.032*
H48B	0.5795	1.1375	0.0629	0.032*
H48C	0.5939	1.1359	0.1767	0.032*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Au1	0.01788 (17)	0.01562 (19)	0.0392 (2)	−0.00083 (16)	−0.00135 (14)	−0.00250 (18)
I1	0.0202 (4)	0.0213 (3)	0.0393 (5)	0.0002 (4)	0.0006 (4)	0.0055 (4)
I2	0.0205 (4)	0.0206 (4)	0.0395 (5)	−0.0010 (4)	0.0013 (4)	−0.0065 (4)
I3	0.0128 (2)	0.0125 (3)	0.0259 (3)	−0.0002 (2)	0.0008 (2)	−0.0014 (3)
N11	0.018 (5)	0.010 (4)	0.027 (6)	0.004 (4)	0.001 (4)	−0.002 (4)
C12	0.022 (7)	0.014 (5)	0.018 (6)	−0.004 (5)	−0.002 (5)	0.000 (5)
C13	0.015 (6)	0.019 (6)	0.019 (7)	−0.004 (5)	−0.001 (5)	−0.005 (5)
C14	0.020 (7)	0.014 (5)	0.019 (7)	−0.004 (5)	0.002 (5)	−0.002 (5)
C15	0.014 (6)	0.023 (7)	0.025 (7)	0.002 (5)	0.005 (5)	0.003 (6)
C16	0.020 (7)	0.022 (6)	0.015 (6)	0.001 (5)	0.000 (5)	−0.003 (5)
C17	0.020 (7)	0.018 (6)	0.041 (9)	0.006 (5)	−0.007 (6)	0.000 (6)
C18	0.024 (7)	0.019 (7)	0.033 (8)	−0.002 (6)	0.006 (6)	−0.004 (6)
N21	0.024 (6)	0.013 (4)	0.020 (6)	0.000 (4)	0.002 (5)	0.000 (4)
C22	0.015 (6)	0.023 (6)	0.014 (6)	0.003 (5)	0.002 (5)	−0.002 (5)
C23	0.024 (7)	0.023 (6)	0.017 (7)	−0.004 (5)	−0.002 (5)	0.001 (5)
C24	0.018 (6)	0.015 (5)	0.024 (7)	0.000 (5)	0.010 (5)	−0.004 (5)
C25	0.017 (6)	0.009 (5)	0.028 (7)	0.004 (4)	0.001 (5)	0.004 (4)
C26	0.015 (6)	0.012 (5)	0.025 (7)	0.003 (4)	−0.005 (5)	−0.003 (5)
C27	0.013 (6)	0.024 (6)	0.031 (8)	−0.002 (5)	−0.003 (5)	0.006 (5)
C28	0.030 (7)	0.010 (5)	0.038 (9)	−0.002 (5)	0.006 (6)	−0.003 (5)
N31	0.018 (5)	0.009 (4)	0.016 (5)	0.000 (4)	0.001 (4)	−0.004 (4)
C32	0.013 (6)	0.019 (6)	0.028 (8)	−0.001 (5)	−0.003 (5)	0.003 (5)
C33	0.016 (6)	0.020 (6)	0.019 (6)	0.001 (5)	−0.001 (5)	−0.001 (5)
C34	0.030 (7)	0.006 (5)	0.014 (6)	0.000 (5)	−0.003 (5)	0.000 (5)
C35	0.016 (6)	0.016 (5)	0.018 (6)	−0.008 (5)	0.001 (5)	−0.001 (5)
C36	0.012 (6)	0.020 (6)	0.015 (6)	−0.001 (4)	0.000 (4)	−0.002 (4)
C37	0.016 (7)	0.025 (7)	0.031 (8)	0.004 (5)	−0.005 (5)	−0.003 (5)
C38	0.033 (7)	0.008 (5)	0.029 (7)	0.001 (5)	0.001 (6)	0.000 (5)
N41	0.019 (6)	0.013 (4)	0.022 (6)	−0.002 (4)	0.000 (4)	0.004 (4)
C42	0.019 (7)	0.011 (5)	0.028 (7)	0.002 (5)	0.004 (5)	0.000 (5)
C43	0.006 (6)	0.015 (5)	0.025 (7)	0.002 (4)	0.003 (5)	0.003 (5)
C44	0.017 (6)	0.014 (5)	0.009 (5)	0.003 (5)	0.004 (4)	0.002 (4)
C45	0.016 (2)	0.016 (2)	0.016 (2)	0.00001 (15)	0.00058 (17)	0.00001 (15)
C46	0.012 (6)	0.017 (6)	0.034 (8)	−0.001 (5)	0.008 (5)	0.005 (5)
C47	0.013 (6)	0.022 (6)	0.034 (8)	−0.003 (5)	−0.003 (5)	0.000 (5)
C48	0.025 (7)	0.020 (6)	0.020 (7)	0.006 (6)	0.000 (5)	0.008 (5)

Geometric parameters (Å, º)

Au1—I1	2.5452 (17)	C15—H15	0.9500
Au1—I2	2.5498 (17)	C16—H16	0.9500
N11—C16	1.334 (17)	C17—H17A	0.9800
N11—C12	1.354 (17)	C17—H17B	0.9800
C12—C13	1.358 (17)	C17—H17C	0.9800
C13—C14	1.421 (18)	C18—H18A	0.9800
C13—C17	1.49 (2)	C18—H18B	0.9800
C14—C15	1.41 (2)	C18—H18C	0.9800
C14—C18	1.508 (17)	C22—H22	0.9500
C15—C16	1.364 (18)	C25—H25	0.9500
N21—C22	1.335 (18)	C26—H26	0.9500
N21—C26	1.337 (17)	C27—H27A	0.9800
C22—C23	1.385 (18)	C27—H27B	0.9800
C23—C24	1.39 (2)	C27—H27C	0.9800
C23—C27	1.52 (2)	C28—H28A	0.9800
C24—C25	1.409 (19)	C28—H28B	0.9800
C24—C28	1.493 (17)	C28—H28C	0.9800
C25—C26	1.383 (15)	N31—H31	0.8800
N31—C36	1.334 (16)	C32—H32	0.9500
N31—C32	1.341 (18)	C35—H35	0.9500
C32—C33	1.379 (17)	C36—H36	0.9500
C33—C34	1.382 (19)	C37—H37A	0.9800
C33—C37	1.512 (19)	C37—H37B	0.9800
C34—C35	1.404 (19)	C37—H37C	0.9800
C34—C38	1.480 (16)	C38—H38A	0.9800
C35—C36	1.382 (16)	C38—H38B	0.9800
N41—C42	1.344 (18)	C38—H38C	0.9800
N41—C46	1.345 (17)	C42—H42	0.9500
C42—C43	1.386 (17)	C45—H45	0.9500
C43—C44	1.400 (17)	C46—H46	0.9500
C43—C47	1.51 (2)	C47—H47A	0.9800
C44—C45	1.369 (19)	C47—H47B	0.9800
C44—C48	1.504 (17)	C47—H47C	0.9800
C45—C46	1.382 (16)	C48—H48A	0.9800
N11—H11	0.8800	C48—H48B	0.9800
C12—H12	0.9500	C48—H48C	0.9800
I1—Au1—I2	178.85 (4)	H18A—C18—H18C	109.5
C16—N11—C12	120.7 (10)	H18B—C18—H18C	109.5
N11—C12—C13	122.5 (12)	N21—C22—H22	117.6
C12—C13—C14	117.7 (12)	C23—C22—H22	117.6
C12—C13—C17	121.7 (12)	C26—C25—H25	120.2
C14—C13—C17	120.4 (12)	C24—C25—H25	120.2
C15—C14—C13	118.5 (12)	N21—C26—H26	118.3
C15—C14—C18	119.9 (12)	C25—C26—H26	118.3
C13—C14—C18	121.5 (13)	C23—C27—H27A	109.5
C16—C15—C14	119.7 (13)	C23—C27—H27B	109.5
N11—C16—C15	120.9 (12)	H27A—C27—H27B	109.5
C22—N21—C26	116.7 (11)	C23—C27—H27C	109.5
N21—C22—C23	124.8 (13)	H27A—C27—H27C	109.5
C22—C23—C24	118.5 (13)	H27B—C27—H27C	109.5
C22—C23—C27	119.5 (13)	C24—C28—H28A	109.5
C24—C23—C27	121.9 (12)	C24—C28—H28B	109.5
C23—C24—C25	117.2 (12)	H28A—C28—H28B	109.5
C23—C24—C28	122.1 (12)	C24—C28—H28C	109.5
C25—C24—C28	120.7 (12)	H28A—C28—H28C	109.5
C26—C25—C24	119.5 (12)	H28B—C28—H28C	109.5
N21—C26—C25	123.3 (12)	C36—N31—H31	119.0
C36—N31—C32	122.0 (11)	C32—N31—H31	119.0
N31—C32—C33	121.2 (12)	N31—C32—H32	119.4
C32—C33—C34	118.8 (12)	C33—C32—H32	119.4
C32—C33—C37	119.5 (12)	C36—C35—H35	119.8
C34—C33—C37	121.8 (12)	C34—C35—H35	119.8
C33—C34—C35	118.6 (11)	N31—C36—H36	120.5
C33—C34—C38	120.4 (12)	C35—C36—H36	120.5
C35—C34—C38	121.1 (12)	C33—C37—H37A	109.5
C36—C35—C34	120.3 (12)	C33—C37—H37B	109.5
N31—C36—C35	119.0 (12)	H37A—C37—H37B	109.5
C42—N41—C46	117.2 (10)	C33—C37—H37C	109.5
N41—C42—C43	124.3 (12)	H37A—C37—H37C	109.5
C42—C43—C44	118.0 (12)	H37B—C37—H37C	109.5
C42—C43—C47	119.0 (11)	C34—C38—H38A	109.5
C44—C43—C47	122.9 (12)	C34—C38—H38B	109.5
C45—C44—C43	117.1 (11)	H38A—C38—H38B	109.5
C45—C44—C48	123.2 (11)	C34—C38—H38C	109.5
C43—C44—C48	119.7 (12)	H38A—C38—H38C	109.5
C44—C45—C46	122.1 (12)	H38B—C38—H38C	109.5
N41—C46—C45	121.2 (12)	N41—C42—H42	117.8
C16—N11—H11	119.6	C43—C42—H42	117.8
C12—N11—H11	119.6	C44—C45—H45	119.0
N11—C12—H12	118.8	C46—C45—H45	119.0
C13—C12—H12	118.8	N41—C46—H46	119.4
C16—C15—H15	120.2	C45—C46—H46	119.4
C14—C15—H15	120.2	C43—C47—H47A	109.5
N11—C16—H16	119.6	C43—C47—H47B	109.5
C15—C16—H16	119.6	H47A—C47—H47B	109.5
C13—C17—H17A	109.5	C43—C47—H47C	109.5
C13—C17—H17B	109.5	H47A—C47—H47C	109.5
H17A—C17—H17B	109.5	H47B—C47—H47C	109.5
C13—C17—H17C	109.5	C44—C48—H48A	109.5
H17A—C17—H17C	109.5	C44—C48—H48B	109.5
H17B—C17—H17C	109.5	H48A—C48—H48B	109.5
C14—C18—H18A	109.5	C44—C48—H48C	109.5
C14—C18—H18B	109.5	H48A—C48—H48C	109.5
H18A—C18—H18B	109.5	H48B—C48—H48C	109.5
C14—C18—H18C	109.5
C16—N11—C12—C13	0 (2)	C36—N31—C32—C33	−2 (2)
N11—C12—C13—C14	−2 (2)	N31—C32—C33—C34	0 (2)
N11—C12—C13—C17	−178.8 (14)	N31—C32—C33—C37	−179.5 (14)
C12—C13—C14—C15	2 (2)	C32—C33—C34—C35	1 (2)
C17—C13—C14—C15	178.9 (14)	C37—C33—C34—C35	−178.7 (13)
C12—C13—C14—C18	178.1 (13)	C32—C33—C34—C38	179.8 (13)
C17—C13—C14—C18	−5 (2)	C37—C33—C34—C38	0 (2)
C13—C14—C15—C16	−1 (2)	C33—C34—C35—C36	−1.3 (19)
C18—C14—C15—C16	−176.2 (13)	C38—C34—C35—C36	−179.8 (12)
C12—N11—C16—C15	2 (2)	C32—N31—C36—C35	2.3 (19)
C14—C15—C16—N11	−2 (2)	C34—C35—C36—N31	−0.4 (19)
C26—N21—C22—C23	0 (2)	C46—N41—C42—C43	−3 (2)
N21—C22—C23—C24	0 (2)	N41—C42—C43—C44	1 (2)
N21—C22—C23—C27	179.8 (14)	N41—C42—C43—C47	179.5 (14)
C22—C23—C24—C25	0.4 (19)	C42—C43—C44—C45	0.3 (19)
C27—C23—C24—C25	−178.9 (13)	C47—C43—C44—C45	−177.6 (13)
C22—C23—C24—C28	179.5 (12)	C42—C43—C44—C48	180.0 (12)
C27—C23—C24—C28	0 (2)	C47—C43—C44—C48	2 (2)
C23—C24—C25—C26	−1 (2)	C43—C44—C45—C46	−1 (2)
C28—C24—C25—C26	179.5 (12)	C48—C44—C45—C46	179.6 (13)
C22—N21—C26—C25	−1 (2)	C42—N41—C46—C45	2 (2)
C24—C25—C26—N21	2 (2)	C44—C45—C46—N41	0 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N11—H11···N21	0.88	1.90	2.767 (13)	166
N31—H31···N41	0.88	1.89	2.753 (14)	166
C12—H12···I3	0.95	3.03	3.845 (13)	145
C16—H16···I3^i	0.95	2.98	3.703 (13)	134
C22—H22···I3	0.95	3.07	3.971 (14)	160
C32—H32···I3^i	0.95	3.00	3.867 (15)	152
C36—H36···I3	0.95	3.15	3.755 (13)	123
C37—H37A···I3^i	0.98	3.16	4.077 (14)	157
C42—H42···I3^i	0.95	3.13	3.995 (14)	151
C46—H46···I3	0.95	3.13	3.850 (13)	134
C38—H38A···I2	0.98	3.25	4.191 (15)	162
C27—H27B···Au1	0.98	3.15	3.862 (14)	131
C28—H28A···Au1	0.98	3.30	4.181 (15)	150
C47—H47B···Au1^ii	0.98	3.23	4.020 (14)	139
C48—H48C···Au1^ii	0.98	3.35	4.164 (16)	142

Symmetry codes: (i) x+1, y, z; (ii) x+1, y+1, z.

Dipyridinegold(I) diiodidoaurate(I) (3)

Crystal data

[Au(C5H5N)2][AuI2]	Dx = 3.555 Mg m^−3
Mr = 805.93	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pnnm	Cell parameters from 6515 reflections
a = 7.1692 (3) Å	θ = 2.9–30.5°
b = 14.2434 (6) Å	µ = 23.54 mm^−1
c = 14.7445 (6) Å	T = 100 K
V = 1505.61 (10) Å^3	Lath, pale yellow
Z = 4	0.28 × 0.18 × 0.04 mm
F(000) = 1392

Data collection

Oxford Diffraction Xcalibur Eos diffractometer	2339 independent reflections
Radiation source: fine-focus sealed X-ray tube	2081 reflections with I > 2σ(I)
Detector resolution: 16.1419 pixels mm^-1	Rint = 0.050
ω scan	θmax = 31.1°, θmin = 2.8°
Absorption correction: multi-scan (CrysAlis PRO; Rigaku OD, 2015)	h = −9→10
Tmin = 0.204, Tmax = 1.000	k = −19→19
22617 measured reflections	l = −21→21

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F^2 > 2σ(F^2)] = 0.025	w = 1/[σ^2(Fo^2) + (0.023P)^2 + 2.7451P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.056	(Δ/σ)max < 0.001
S = 1.07	Δρmax = 2.25 e Å^−3
2339 reflections	Δρmin = −1.95 e Å^−3
80 parameters	Extinction correction: SHELXL2014 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.00029 (3)

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Au1	0.37960 (3)	0.23901 (2)	0.5000	0.01197 (7)
I1	0.65999 (5)	0.34946 (3)	0.5000	0.01650 (10)
I2	0.11965 (5)	0.11783 (3)	0.5000	0.01793 (10)
Au2	0.13467 (3)	0.40791 (2)	0.5000	0.01174 (7)
N11	0.1390 (4)	0.4020 (3)	0.3618 (2)	0.0138 (7)
C12	0.0553 (6)	0.3289 (3)	0.3192 (3)	0.0174 (9)
H12	−0.0122	0.2842	0.3540	0.021*
C13	0.0661 (7)	0.3181 (4)	0.2265 (3)	0.0235 (10)
H13	0.0074	0.2662	0.1980	0.028*
C14	0.1624 (7)	0.3830 (4)	0.1754 (3)	0.0263 (11)
H14	0.1704	0.3764	0.1114	0.032*
C15	0.2473 (6)	0.4578 (4)	0.2188 (3)	0.0215 (10)
H15	0.3148	0.5034	0.1852	0.026*
C16	0.2323 (6)	0.4650 (3)	0.3123 (3)	0.0176 (9)
H16	0.2902	0.5164	0.3421	0.021*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Au1	0.01460 (12)	0.01236 (13)	0.00896 (12)	−0.00145 (8)	0.000	0.000
I1	0.01518 (19)	0.0186 (2)	0.0157 (2)	−0.00479 (15)	0.000	0.000
I2	0.0225 (2)	0.0150 (2)	0.0163 (2)	−0.00686 (15)	0.000	0.000
Au2	0.01499 (12)	0.01424 (13)	0.00600 (11)	0.00092 (8)	0.000	0.000
N11	0.0148 (17)	0.019 (2)	0.0075 (16)	0.0038 (14)	0.0008 (12)	0.0004 (14)
C12	0.024 (2)	0.017 (2)	0.011 (2)	0.0014 (18)	0.0013 (17)	−0.0001 (17)
C13	0.030 (2)	0.026 (3)	0.015 (2)	0.001 (2)	−0.0043 (19)	−0.004 (2)
C14	0.029 (3)	0.041 (3)	0.010 (2)	0.000 (2)	0.0018 (18)	−0.005 (2)
C15	0.024 (2)	0.027 (3)	0.013 (2)	−0.0064 (19)	0.0014 (17)	0.005 (2)
C16	0.018 (2)	0.023 (2)	0.012 (2)	−0.0016 (18)	0.0008 (16)	0.0004 (19)

Geometric parameters (Å, º)

Au1—I2	2.5401 (5)	C12—H12	0.9500
Au1—I1	2.5526 (4)	C13—C14	1.378 (7)
Au1—Au2	2.9784 (3)	C13—H13	0.9500
Au2—N11	2.040 (4)	C14—C15	1.385 (7)
Au2—Au2^i	3.2575 (5)	C14—H14	0.9500
N11—C16	1.336 (6)	C15—C16	1.386 (6)
N11—C12	1.356 (6)	C15—H15	0.9500
C12—C13	1.377 (6)	C16—H16	0.9500
I2—Au1—I1	175.243 (18)	C12—C13—C14	119.8 (5)
I2—Au1—Au2	96.679 (13)	C12—C13—H13	120.1
I1—Au1—Au2	88.078 (13)	C14—C13—H13	120.1
N11^ii—Au2—N11	175.0 (2)	C13—C14—C15	118.9 (4)
N11—Au2—Au1	87.59 (10)	C13—C14—H14	120.6
N11—Au2—Au2^i	92.41 (10)	C15—C14—H14	120.6
Au1—Au2—Au2^i	179.771 (13)	C14—C15—C16	118.9 (4)
C16—N11—C12	118.9 (4)	C14—C15—H15	120.6
C16—N11—Au2	121.7 (3)	C16—C15—H15	120.6
C12—N11—Au2	119.2 (3)	N11—C16—C15	122.2 (4)
N11—C12—C13	121.3 (4)	N11—C16—H16	118.9
N11—C12—H12	119.3	C15—C16—H16	118.9
C13—C12—H12	119.3
C16—N11—C12—C13	0.6 (6)	C13—C14—C15—C16	−0.1 (7)
Au2—N11—C12—C13	−175.2 (4)	C12—N11—C16—C15	−0.4 (6)
N11—C12—C13—C14	−0.5 (7)	Au2—N11—C16—C15	175.2 (3)
C12—C13—C14—C15	0.3 (8)	C14—C15—C16—N11	0.2 (7)

Symmetry codes: (i) −x, −y+1, −z+1; (ii) x, y, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C16—H16···I1^iii	0.95	3.03	3.904 (5)	153
C13—H13···Au1^iv	0.95	3.06	3.689 (5)	125
C14—H14···Au1^iv	0.95	3.12	3.717 (5)	122
C15—H15···I2^v	0.95	3.21	4.064 (5)	150

Symmetry codes: (iii) −x+1, −y+1, −z+1; (iv) x−1/2, −y+1/2, z−1/2; (v) −x+1/2, y+1/2, −z+1/2.