Reconstructive phase transition in (NH4)3TiF7 accompanied by the ordering of TiF6 octahedra

Molokeev, M.; Misjul, S.V.; Flerov, I.N.; Laptash, N.M.

doi:10.1107/S2052520614021192

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Reconstructive phase transition in (NH₄)₃TiF₇ accompanied by the ordering of TiF₆ octahedra

M. Molokeev, S. V. Misjul, I. N. Flerov and N. M. Laptash

An unusual phase transition P4/mnc → $Pa\bar 3$ has been detected after cooling the (NH₄)₃TiF₇ compound. Some TiF₆ octahedra, which are disordered in the room-temperature tetragonal structure, become ordered in the low-temperature cubic phase due to the disappearance of the fourfold axis. Other TiF₆ octahedra undergo large rotations resulting in huge displacements of the F atoms by 1.5–1.8 Å that implies a reconstructive phase transition. It was supposed that phases P4/mbm and $Pm\bar 3m$ could be a high-temperature phase and a parent phase, respectively, in (NH₄)₃TiF₇. Therefore, the sequence of phase transitions can be written as $Pm\bar 3m$ → P4/mbm → P4/mnc → $Pa\bar 3$ . The interrelation between (NH₄)₃TiF₇, (NH₄)₃GeF₇ and (NH₄)₃PbF₇ is found, which allows us to suppose phase transitions in relative compounds.

Keywords: reconstructive phase transition; ammonium heptafluorotitanate; order–disorder transition.

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S2052520614021192/bp5070sup1.cif Contains datablocks global, I, II
	Structure factor file (CIF format) https://doi.org/10.1107/S2052520614021192/bp5070Isup2.hkl Contains datablock I
	Structure factor file (CIF format) https://doi.org/10.1107/S2052520614021192/bp5070IIsup3.hkl Contains datablock II
	Rietveld powder data file (CIF format) https://doi.org/10.1107/S2052520614021192/bp5070IIsup4.rtv Contains datablock II

CCDC references: 1025663; 1025664

Experimental top

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 1.

Results and discussion top

Computing details top

Data collection: APEX2 (Bruker, 2008) for (I). Cell refinement: APEX2 (Bruker, 2008) for (I). Data reduction: SAINT (Bruker, 2008) for (I). Program(s) used to solve structure: SHELXS97 (Sheldrick, 2008) for (I). Program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) for (I). Molecular graphics: DIAMOND (Brandenburg, 2005) for (I). Software used to prepare material for publication: publCIF (Westrip, 2010) for (I).

Figures top

(I) Ammonium heptafluorotitanate top

Crystal data top

F₆Ti·F·3(H₄N)	D_x = 1.870 Mg m⁻³
M_r = 235.03	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, P4/mnc	Cell parameters from 1741 reflections
Hall symbol: -P 4 2n	θ = 3.4–25.0°
a = 11.9597 (19) Å	µ = 1.10 mm⁻¹
c = 11.6747 (19) Å	T = 296 K
V = 1669.9 (5) Å³	Bulk, colourless
Z = 8	0.3 × 0.2 × 0.2 mm
F(000) = 944

Data collection top

Bruker APEX-II CCD diffractometer	959 independent reflections
Radiation source: fine-focus sealed tube	483 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.075
ϕ and ω scans	θ_max = 26.9°, θ_min = 2.4°
Absorption correction: multi-scan SADABS2004/1. Bruker AXS Inc., Madison, Wisconsin, USA, 2004	h = −15→15
T_min = 0.611, T_max = 0.746	k = −15→15
13112 measured reflections	l = −14→14

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F² > 2σ(F²)] = 0.048	Only H-atom coordinates refined
wR(F²) = 0.152	w = 1/[σ²(F_o²) + (0.0536P)² + 3.8962P] where P = (F_o² + 2F_c²)/3
S = 1.07	(Δ/σ)_max = 0.004
959 reflections	Δρ_max = 0.52 e Å⁻³
100 parameters	Δρ_min = −0.40 e Å⁻³
7 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0028 (7)

Crystal data top

F₆Ti·F·3(H₄N)	Z = 8
M_r = 235.03	Mo Kα radiation
Tetragonal, P4/mnc	µ = 1.10 mm⁻¹
a = 11.9597 (19) Å	T = 296 K
c = 11.6747 (19) Å	0.3 × 0.2 × 0.2 mm
V = 1669.9 (5) Å³

Data collection top

Bruker APEX-II CCD diffractometer	959 independent reflections
Absorption correction: multi-scan SADABS2004/1. Bruker AXS Inc., Madison, Wisconsin, USA, 2004	483 reflections with I > 2σ(I)
T_min = 0.611, T_max = 0.746	R_int = 0.075
13112 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.048	7 restraints
wR(F²) = 0.152	Only H-atom coordinates refined
S = 1.07	Δρ_max = 0.52 e Å⁻³
959 reflections	Δρ_min = −0.40 e Å⁻³
100 parameters

Special details top

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

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
Ti1	0.0000	0.0000	0.0000	0.0272 (6)
Ti2	0.5000	0.0000	0.0000	0.0286 (5)
Ti3	0.0000	0.0000	0.5000	0.0289 (6)
N1	0.2850 (7)	0.2606 (6)	0.0000	0.072 (2)
N2	0.0121 (6)	0.2468 (5)	0.2206 (5)	0.0702 (16)
F1	0.1326 (3)	0.0788 (4)	0.0000	0.0669 (14)
F2	0.6365 (4)	0.0726 (4)	0.0000	0.0755 (15)
F3	0.0000	0.0000	0.1578 (4)	0.0620 (18)
F4	0.4467 (3)	0.0950 (3)	0.1117 (3)	0.0796 (12)
F5	−0.031 (5)	0.116 (3)	0.407 (3)	0.068 (10)	0.25
F6	0.014 (4)	0.1430 (17)	0.433 (2)	0.051 (5)	0.25
F7	0.061 (4)	0.095 (5)	0.396 (3)	0.076 (7)	0.25
F8	0.2399 (3)	0.2601 (3)	0.2500	0.0751 (15)
H21	0.003 (6)	0.196 (4)	0.264 (4)	0.090*
H22	−0.023 (5)	0.289 (4)	0.259 (5)	0.090*
H23	−0.010 (5)	0.210 (5)	0.168 (4)	0.090*
H24	0.075 (2)	0.268 (5)	0.226 (6)	0.090*
H11	0.240 (4)	0.250 (5)	0.049 (4)	0.090*
H13	0.313 (7)	0.321 (3)	0.0000	0.090*
H14	0.324 (6)	0.206 (5)	0.0000	0.090*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ti1	0.0255 (7)	0.0255 (7)	0.0305 (11)	0.000	0.000	0.000
Ti2	0.0292 (9)	0.0278 (9)	0.0289 (8)	−0.0014 (7)	0.000	0.000
Ti3	0.0304 (8)	0.0304 (8)	0.0259 (11)	0.000	0.000	0.000
N1	0.040 (4)	0.042 (4)	0.133 (8)	−0.008 (3)	0.000	0.000
N2	0.108 (5)	0.052 (3)	0.051 (3)	0.001 (3)	0.001 (4)	−0.008 (2)
F1	0.048 (3)	0.063 (3)	0.090 (3)	−0.025 (2)	0.000	0.000
F2	0.050 (3)	0.090 (4)	0.086 (3)	−0.031 (2)	0.000	0.000
F3	0.076 (3)	0.076 (3)	0.033 (3)	0.000	0.000	0.000
F4	0.094 (3)	0.075 (2)	0.069 (2)	0.0024 (19)	0.0164 (19)	−0.032 (2)
F5	0.08 (3)	0.06 (2)	0.060 (17)	−0.001 (16)	0.018 (15)	0.038 (16)
F6	0.049 (15)	0.021 (7)	0.083 (13)	−0.002 (11)	0.001 (12)	0.015 (7)
F7	0.069 (18)	0.09 (2)	0.069 (14)	−0.039 (13)	−0.022 (13)	0.052 (14)
F8	0.076 (2)	0.076 (2)	0.074 (3)	0.006 (2)	0.0041 (18)	0.0041 (18)

Geometric parameters (Å, º) top

Ti1—F3ⁱ	1.842 (5)	Ti3—F5^ix	1.80 (2)
Ti1—F3	1.842 (5)	Ti3—F5^x	1.80 (2)
Ti1—F1ⁱ	1.845 (4)	Ti3—F5^xi	1.80 (2)
Ti1—F1ⁱⁱ	1.845 (4)	Ti3—F5^xii	1.80 (2)
Ti1—F1ⁱⁱⁱ	1.845 (4)	Ti3—F7^viii	1.819 (16)
Ti1—F1	1.845 (4)	Ti3—F7^ix	1.819 (16)
Ti2—F4^iv	1.843 (3)	Ti3—F7^vii	1.819 (16)
Ti2—F4^v	1.843 (3)	Ti3—F7ⁱⁱⁱ	1.819 (16)
Ti2—F4^vi	1.843 (3)	F5—F6	0.70 (5)
Ti2—F4	1.843 (3)	F5—F7ⁱⁱⁱ	1.02 (2)
Ti2—F2^iv	1.850 (4)	F5—F7	1.13 (4)
Ti2—F2	1.850 (4)	F6—F7	0.91 (8)
Ti3—F5	1.80 (2)	F6—F6^viii	1.57 (6)
Ti3—F5^vii	1.80 (2)	F6—F7ⁱⁱⁱ	1.69 (4)
Ti3—F5ⁱⁱⁱ	1.80 (2)	F7—F5^xi	1.02 (2)
Ti3—F5^viii	1.80 (2)	F7—F6^xi	1.69 (4)

F3ⁱ—Ti1—F3	180.0	F5ⁱⁱⁱ—Ti3—F7^viii	147.2 (8)
F3ⁱ—Ti1—F1ⁱ	90.0	F5^viii—Ti3—F7^viii	36.4 (12)
F3—Ti1—F1ⁱ	90.0	F5^ix—Ti3—F7^viii	143.6 (12)
F3ⁱ—Ti1—F1ⁱⁱ	90.0	F5^x—Ti3—F7^viii	91.7 (11)
F3—Ti1—F1ⁱⁱ	90.0	F5^xi—Ti3—F7^viii	88.3 (11)
F1ⁱ—Ti1—F1ⁱⁱ	90.0	F5^xii—Ti3—F7^viii	89.7 (10)
F3ⁱ—Ti1—F1ⁱⁱⁱ	90.0	F5—Ti3—F7^ix	89.7 (10)
F3—Ti1—F1ⁱⁱⁱ	90.0	F5^vii—Ti3—F7^ix	147.2 (8)
F1ⁱ—Ti1—F1ⁱⁱⁱ	90.0	F5ⁱⁱⁱ—Ti3—F7^ix	32.8 (8)
F1ⁱⁱ—Ti1—F1ⁱⁱⁱ	180.0 (2)	F5^viii—Ti3—F7^ix	143.6 (12)
F3ⁱ—Ti1—F1	90.0	F5^ix—Ti3—F7^ix	36.4 (12)
F3—Ti1—F1	90.0	F5^x—Ti3—F7^ix	88.3 (11)
F1ⁱ—Ti1—F1	180.0	F5^xi—Ti3—F7^ix	91.7 (11)
F1ⁱⁱ—Ti1—F1	90.0	F5^xii—Ti3—F7^ix	90.3 (10)
F1ⁱⁱⁱ—Ti1—F1	90.0	F7^viii—Ti3—F7^ix	180.000 (2)
F4^iv—Ti2—F4^v	90.0 (2)	F5—Ti3—F7^vii	147.2 (8)
F4^iv—Ti2—F4^vi	90.0 (2)	F5^vii—Ti3—F7^vii	36.4 (12)
F4^v—Ti2—F4^vi	180.0 (3)	F5ⁱⁱⁱ—Ti3—F7^vii	143.6 (12)
F4^iv—Ti2—F4	180.0	F5^viii—Ti3—F7^vii	91.7 (11)
F4^v—Ti2—F4	90.0 (2)	F5^ix—Ti3—F7^vii	88.3 (11)
F4^vi—Ti2—F4	90.0 (2)	F5^x—Ti3—F7^vii	89.7 (10)
F4^iv—Ti2—F2^iv	90.91 (15)	F5^xi—Ti3—F7^vii	90.3 (10)
F4^v—Ti2—F2^iv	89.09 (15)	F5^xii—Ti3—F7^vii	32.8 (8)
F4^vi—Ti2—F2^iv	90.91 (15)	F7^viii—Ti3—F7^vii	63.3 (16)
F4—Ti2—F2^iv	89.10 (15)	F7^ix—Ti3—F7^vii	116.7 (16)
F4^iv—Ti2—F2	89.09 (15)	F5—Ti3—F7ⁱⁱⁱ	32.8 (8)
F4^v—Ti2—F2	90.91 (15)	F5^vii—Ti3—F7ⁱⁱⁱ	143.6 (12)
F4^vi—Ti2—F2	89.09 (15)	F5ⁱⁱⁱ—Ti3—F7ⁱⁱⁱ	36.4 (12)
F4—Ti2—F2	90.90 (15)	F5^viii—Ti3—F7ⁱⁱⁱ	88.3 (11)
F2^iv—Ti2—F2	180.0	F5^ix—Ti3—F7ⁱⁱⁱ	91.7 (11)
F5—Ti3—F5^vii	111.5 (14)	F5^x—Ti3—F7ⁱⁱⁱ	90.3 (10)
F5—Ti3—F5ⁱⁱⁱ	68.5 (14)	F5^xi—Ti3—F7ⁱⁱⁱ	89.7 (10)
F5^vii—Ti3—F5ⁱⁱⁱ	180.000 (3)	F5^xii—Ti3—F7ⁱⁱⁱ	147.2 (8)
F5—Ti3—F5^viii	74 (3)	F7^viii—Ti3—F7ⁱⁱⁱ	116.7 (16)
F5^vii—Ti3—F5^viii	68.5 (14)	F7^ix—Ti3—F7ⁱⁱⁱ	63.3 (16)
F5ⁱⁱⁱ—Ti3—F5^viii	111.5 (14)	F7^vii—Ti3—F7ⁱⁱⁱ	180.0 (18)
F5—Ti3—F5^ix	106 (3)	F6—F5—F7ⁱⁱⁱ	159 (6)
F5^vii—Ti3—F5^ix	111.5 (14)	F6—F5—F7	54 (6)
F5ⁱⁱⁱ—Ti3—F5^ix	68.5 (14)	F7ⁱⁱⁱ—F5—F7	125 (6)
F5^viii—Ti3—F5^ix	180.000 (3)	F6—F5—Ti3	86 (4)
F5—Ti3—F5^x	111.5 (14)	F7ⁱⁱⁱ—F5—Ti3	74.4 (17)
F5^vii—Ti3—F5^x	106 (3)	F7—F5—Ti3	72.5 (15)
F5ⁱⁱⁱ—Ti3—F5^x	74 (3)	F5—F6—F7	89 (5)
F5^viii—Ti3—F5^x	68.5 (14)	F5—F6—F6^viii	116 (4)
F5^ix—Ti3—F5^x	111.5 (14)	F7—F6—F6^viii	118 (2)
F5—Ti3—F5^xi	68.5 (14)	F7—F6—F7ⁱⁱⁱ	89 (3)
F5^vii—Ti3—F5^xi	74 (3)	F6^viii—F6—F7ⁱⁱⁱ	105 (2)
F5ⁱⁱⁱ—Ti3—F5^xi	106 (3)	F5—F6—Ti3	72 (3)
F5^viii—Ti3—F5^xi	111.5 (14)	F7—F6—Ti3	71.4 (19)
F5^ix—Ti3—F5^xi	68.5 (14)	F6^viii—F6—Ti3	65.4 (8)
F5^x—Ti3—F5^xi	180.000 (2)	F7ⁱⁱⁱ—F6—Ti3	60.7 (11)
F5—Ti3—F5^xii	180.000 (5)	F6—F7—F5^xi	144 (5)
F5^vii—Ti3—F5^xii	68.5 (14)	F5^xi—F7—F5	141 (3)
F5ⁱⁱⁱ—Ti3—F5^xii	111.5 (14)	F6—F7—F6^xi	136 (4)
F5^viii—Ti3—F5^xii	106 (3)	F5—F7—F6^xi	135.0 (18)
F5^ix—Ti3—F5^xii	74 (3)	F6—F7—Ti3	80 (2)
F5^x—Ti3—F5^xii	68.5 (14)	F5^xi—F7—Ti3	72.8 (16)
F5^xi—Ti3—F5^xii	111.5 (14)	F5—F7—Ti3	71.1 (16)
F5—Ti3—F7^viii	90.3 (10)	F6^xi—F7—Ti3	65.1 (13)
F5^vii—Ti3—F7^viii	32.8 (8)

Symmetry codes: (i) −x, −y, −z; (ii) y, −x, −z; (iii) −y, x, z; (iv) −x+1, −y, −z; (v) x, y, −z; (vi) −x+1, −y, z; (vii) y, −x, −z+1; (viii) x, y, −z+1; (ix) −x, −y, z; (x) −y, x, −z+1; (xi) y, −x, z; (xii) −x, −y, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H11···F1	0.80 (5)	2.48 (6)	2.837 (9)	108 (5)
N1—H11···F8	0.80 (5)	2.35 (5)	2.968 (2)	135 (4)
N1—H11···F2^xiii	0.80 (5)	2.49 (5)	2.823 (9)	107 (4)
N1—H11···F2^xiv	0.80 (5)	2.49 (5)	2.823 (9)	107 (4)
N1—H14···F4	0.80 (5)	2.37 (6)	3.060 (8)	145 (2)
N1—H14···F4^v	0.80 (5)	2.37 (6)	3.060 (8)	145 (2)
N2—H22···F4^xv	0.80 (6)	2.08 (5)	2.833 (7)	158 (6)
N2—H23···F1ⁱⁱⁱ	0.80 (5)	2.32 (5)	3.111 (6)	170 (6)
N2—H24···F8	0.80 (3)	1.99 (3)	2.751 (8)	159 (6)

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

(II) top

Crystal data top

F₆Ti·F·3(H₄N)	Z = 8
M_r = 235.00	D_x = 1.908 Mg m⁻³
Cubic, Pa3	Cu Kα₁₂ radiation, λ = 1.5406, 1.5443 Å
Hall symbol: -P 2ac 2ab 3	T = 143 K
a = 11.78316 (15) Å	colourless
V = 1636.01 (6) Å³	?, ? × ? × ? mm

Data collection top

D8 ADVANCE Bruker diffractometer	Data collection mode: reflection
None monochromator	Scan method: step
Specimen mounting: flat, densely packed	2θ_min = 11.013°, 2θ_max = 139.987°, 2θ_step = 0.016°

Refinement top

R_p = 3.926	Profile function: PearsonVII
R_wp = 4.850	61 parameters
R_exp = 2.213	9 restraints
R_Bragg = 1.79	(Δ/σ)_max = 0.010
χ² = 4.800	Preferred orientation correction: no preferred orientation
8060.88125 data points

Crystal data top

F₆Ti·F·3(H₄N)	Z = 8
M_r = 235.00	Cu Kα₁₂ radiation, λ = 1.5406, 1.5443 Å
Cubic, Pa3	T = 143 K
a = 11.78316 (15) Å	?, ? × ? × ? mm
V = 1636.01 (6) Å³

Data collection top

D8 ADVANCE Bruker diffractometer	Scan method: step
Specimen mounting: flat, densely packed	2θ_min = 11.013°, 2θ_max = 139.987°, 2θ_step = 0.016°
Data collection mode: reflection

Refinement top

R_p = 3.926	χ² = 4.800
R_wp = 4.850	8060.88125 data points
R_exp = 2.213	61 parameters
R_Bragg = 1.79	9 restraints

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	B_iso*/B_eq
Ti1	0	0	0	0
Ti2	0.5	0	0	0
F1	0.15394 (17)	−0.0155 (2)	0.0142 (3)	0
F2	0.3899 (2)	0.0958 (3)	0.05309 (17)	0
F3	0.2569 (3)	0.2569 (3)	0.2569 (3)	0
N	0.2406 (4)	0.2352 (3)	0.4821 (3)	0
H1	0.263145	0.164540	0.500386	4*
H2	0.236375	0.241701	0.406118	4*
H3	0.171917	0.248703	0.512671	4*
H4	0.290951	0.285805	0.509237	4*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ti1	0.0210 (17)	0.0210 (17)	0.0210 (17)	−0.0010 (11)	−0.0010 (11)	−0.0010 (11)
Ti2	0.0143 (17)	0.0143 (17)	0.0143 (17)	−0.0042 (10)	−0.0042 (10)	−0.0042 (10)
F1	0.035 (2)	0.034 (4)	0.053 (4)	0.0183 (19)	−0.009 (2)	−0.0085 (19)
F2	0.031 (3)	0.013 (3)	0.027 (2)	0.0031 (14)	−0.0034 (18)	0.0033 (18)
F3	0.0390 (18)	0.0390 (18)	0.0390 (18)	0.012 (3)	0.012 (3)	0.012 (3)
N	0.028 (9)	0.029 (10)	0.054 (4)	−0.006 (3)	−0.020 (4)	−0.010 (4)

Bond lengths (Å) top

Ti1—F1	1.831 (3)	N—H2	0.9000
Ti2—F2	1.830 (3)	N—H3	0.9000
N—H1	0.9000	N—H4	0.9000

Experimental details

	(I)	(II)
Crystal data
Chemical formula	F₆Ti·F·3(H₄N)	F₆Ti·F·3(H₄N)
M_r	235.03	235.00
Crystal system, space group	Tetragonal, P4/mnc	Cubic, Pa3
Temperature (K)	296	143
a, b, c (Å)	11.9597 (19), 11.9597 (19), 11.6747 (19)	11.78316 (15), 11.78316 (15), 11.78316 (15)
α, β, γ (°)	90, 90, 90	90, 90, 90
V (Å³)	1669.9 (5)	1636.01 (6)
Z	8	8
Radiation type	Mo Kα	Cu Kα₁₂, λ = 1.5406, 1.5443 Å
µ (mm⁻¹)	1.10	–
Specimen shape, size (mm)	0.3 × 0.2 × 0.2	?, ? × ? × ?

Data collection
Diffractometer	Bruker APEX-II CCD diffractometer	D8 ADVANCE Bruker diffractometer
Specimen mounting	–	Flat, densely packed
Data collection mode	–	Reflection
Data collection method	ϕ and ω scans	Step
Absorption correction	Multi-scan SADABS2004/1. Bruker AXS Inc., Madison, Wisconsin, USA, 2004	–
T_min, T_max	0.611, 0.746	–
No. of measured, independent and observed [I > 2σ(I)] reflections	13112, 959, 483	–
R_int	0.075	–
θ values (°)	θ_max = 26.9, θ_min = 2.4	2θ_min = 11.013 2θ_max = 139.987 2θ_step = 0.016
(sin θ/λ)_max (Å⁻¹)	0.637	–

Refinement
R factors and goodness of fit	R[F² > 2σ(F²)] = 0.048, wR(F²) = 0.152, S = 1.07	R_p = 3.926, R_wp = 4.850, R_exp = 2.213, R_Bragg = 1.79, χ² = 4.800
No. of reflections/data points	959	8060.88125
No. of parameters	100	61
No. of restraints	7	9
H-atom treatment	Only H-atom coordinates refined	?
Δρ_max, Δρ_min (e Å⁻³)	0.52, −0.40	–

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2005), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) for (I) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H11···F1	0.80 (5)	2.48 (6)	2.837 (9)	108 (5)
N1—H11···F8	0.80 (5)	2.35 (5)	2.968 (2)	135 (4)
N1—H11···F2ⁱ	0.80 (5)	2.49 (5)	2.823 (9)	107 (4)
N1—H11···F2ⁱⁱ	0.80 (5)	2.49 (5)	2.823 (9)	107 (4)
N1—H14···F4	0.80 (5)	2.37 (6)	3.060 (8)	145 (2)
N1—H14···F4ⁱⁱⁱ	0.80 (5)	2.37 (6)	3.060 (8)	145 (2)
N2—H22···F4^iv	0.80 (6)	2.08 (5)	2.833 (7)	158 (6)
N2—H23···F1^v	0.80 (5)	2.32 (5)	3.111 (6)	170 (6)
N2—H24···F8	0.80 (3)	1.99 (3)	2.751 (8)	159 (6)

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

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