Bis(pyrrolidinium) hexa­chlorido­stannate: a redetermination

The crystal structure of the title compound, (C₄H₁₀N)₂[SnCl₆], has been redetermined at 180 K. All atoms were located with higher precision than the previous structure determined at room temperature [Ishida et al. (2000). J Mol. Struct. 524, 95–103]. In the crystal, the Sn^IV atom is located on a special position of site symmetry 2/m and is coordinated by six Cl atoms in a pseudo-octa­hedral geometry. Of the six Cl atoms, two equivalent axial atoms lie on the mirror plane [Sn—Cl = 2.4281 (6) Å] and the other four equivalent equatorial atoms lie on general positions [Sn—Cl = 2.4285 (4) Å]. The N atom of the pyrrolidinium cation lies on a mirror plane and the other atoms of the cation are disordered over two sites with respect to the mirror plane. Each component of the disordered five-membered rings adopts a twist conformation. The cations and anions are connected via N—H...Cl hydrogen bonds, forming a tape-like structure propagating along [010].

Key indicators

• Single-crystal X-ray study
• T = 180 K
• Mean [sigma](Sn-Cl) = 0.001 Å
• Disorder in main residue
• R factor = 0.024
• wR factor = 0.057
• Data-to-parameter ratio = 19.8

checkCIF/PLATON results

No syntax errors found



Alert level G
PLAT002_ALERT_2_G Number of Distance or Angle Restraints on AtSite          3 Note
PLAT172_ALERT_4_G The CIF-Embedded .res File Contains DFIX Records          2 Report
PLAT232_ALERT_2_G Hirshfeld Test Diff (M-X)  Sn1      --Cl1      .        5.3 s.u.
PLAT300_ALERT_4_G Atom Site Occupancy of C1         Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of C2         Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of C3         Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of C4         Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H1NA       Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H1A        Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H1B        Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H1NB       Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H2A        Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H2B        Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H3A        Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H3B        Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H4A        Constrained at        0.5 Check
PLAT300_ALERT_4_G Atom Site Occupancy of H4B        Constrained at        0.5 Check
PLAT301_ALERT_3_G Main Residue  Disorder ..............(Resd  1  )        80% Note
PLAT720_ALERT_4_G Number of Unusual/Non-Standard Labels ..........          2 Note
PLAT789_ALERT_4_G Atoms with Negative _atom_site_disorder_group  #         14 Check
PLAT811_ALERT_5_G No ADDSYM Analysis: Too Many Excluded Atoms ....          ! Info
PLAT860_ALERT_3_G Number of Least-Squares Restraints .............          2 Note
PLAT910_ALERT_3_G Missing # of FCF Reflection(s) Below Theta(Min).          2 Note

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   0 ALERT level C = Check. Ensure it is not caused by an omission or oversight
  23 ALERT level G = General information/check it is not something unexpected

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
  17 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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Computing details

Data collection: RAPID-AUTO (Rigaku, 2006); cell refinement: RAPID-AUTO (Rigaku, 2006); data reduction: RAPID-AUTO (Rigaku, 2006); program(s) used to solve structure: SHELXT2018/2 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018/3 (Sheldrick, 2015b); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: CrystalStructure (Rigaku, 2018) and PLATON (Spek, 2009).

Bis(pyrrolidinium) hexachloridostannate

Crystal data

(C4H10N)2[SnCl6]	F(000) = 468.00
Mr = 475.67	Dx = 1.843 Mg m^−3
Monoclinic, C2/m	Mo Kα radiation, λ = 0.71075 Å
a = 16.3784 (11) Å	Cell parameters from 5181 reflections
b = 7.3134 (3) Å	θ = 3.1–30.0°
c = 7.1566 (4) Å	µ = 2.41 mm^−1
β = 91.205 (2)°	T = 180 K
V = 857.04 (8) Å^3	Platelet, colorless
Z = 2	0.20 × 0.20 × 0.10 mm

Data collection

Rigaku R-AXIS RAPIDII diffractometer	1308 reflections with I > 2σ(I)
Detector resolution: 10.000 pixels mm^-1	Rint = 0.038
ω scans	θmax = 30.0°, θmin = 3.1°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −22→22
Tmin = 0.579, Tmax = 0.786	k = −10→9
5281 measured reflections	l = −10→10
1343 independent reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.024	Hydrogen site location: mixed
wR(F^2) = 0.057	H atoms treated by a mixture of independent and constrained refinement
S = 1.09	w = 1/[σ^2(Fo^2) + (0.035P)^2 + 0.3195P] where P = (Fo^2 + 2Fc^2)/3
1343 reflections	(Δ/σ)max = 0.001
68 parameters	Δρmax = 0.54 e Å^−3
2 restraints	Δρmin = −1.10 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)
Sn1	0.500000	0.500000	0.000000	0.02448 (8)
Cl1	0.61941 (4)	0.500000	0.20690 (9)	0.03911 (14)
Cl2	0.56208 (3)	0.26144 (5)	−0.18554 (6)	0.03335 (10)
N1	0.61485 (15)	0.000000	0.1846 (3)	0.0378 (5)
H1NA	0.590 (4)	0.082 (6)	0.113 (7)	0.057*	0.5
H1NB	0.595 (4)	−0.111 (5)	0.163 (7)	0.057*	0.5
C1	0.7040 (2)	−0.015 (5)	0.1454 (6)	0.054 (3)	0.5
H1A	0.718653	−0.141991	0.112102	0.065*	0.5
H1B	0.719081	0.067232	0.041717	0.065*	0.5
C2	0.7455 (2)	0.0412 (6)	0.3229 (7)	0.0512 (12)	0.5
H2A	0.750038	0.175930	0.331790	0.061*	0.5
H2B	0.800714	−0.013262	0.334683	0.061*	0.5
C3	0.6886 (2)	−0.0348 (6)	0.4717 (5)	0.0419 (13)	0.5
H3A	0.694280	−0.169065	0.484205	0.050*	0.5
H3B	0.699197	0.023171	0.594843	0.050*	0.5
C4	0.60557 (18)	0.017 (3)	0.3925 (4)	0.034 (3)	0.5
H4A	0.562866	−0.066758	0.437619	0.041*	0.5
H4B	0.591198	0.143984	0.427417	0.041*	0.5

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Sn1	0.02747 (11)	0.01710 (11)	0.02918 (12)	0.000	0.00770 (7)	0.000
Cl1	0.0362 (3)	0.0386 (3)	0.0423 (3)	0.000	−0.0047 (2)	0.000
Cl2	0.0398 (2)	0.02416 (18)	0.0366 (2)	0.00185 (14)	0.01405 (15)	−0.00506 (14)
N1	0.0375 (11)	0.0426 (12)	0.0334 (10)	0.000	0.0050 (8)	0.000
C1	0.0469 (16)	0.059 (10)	0.0573 (18)	0.002 (4)	0.0289 (14)	−0.009 (6)
C2	0.0279 (14)	0.047 (3)	0.079 (3)	−0.0078 (14)	0.0107 (15)	−0.0076 (19)
C3	0.0323 (14)	0.044 (4)	0.0490 (16)	0.0022 (14)	−0.0033 (12)	0.0092 (16)
C4	0.0279 (11)	0.044 (8)	0.0313 (10)	0.006 (3)	0.0072 (8)	0.004 (2)

Geometric parameters (Å, º)

Sn1—Cl1^i	2.4281 (6)	C1—H1A	0.9900
Sn1—Cl1	2.4281 (6)	C1—H1B	0.9900
Sn1—Cl2	2.4285 (4)	C2—C3	1.534 (5)
Sn1—Cl2^i	2.4285 (4)	C2—H2A	0.9900
Sn1—Cl2^ii	2.4285 (4)	C2—H2B	0.9900
Sn1—Cl2^iii	2.4285 (4)	C3—C4	1.512 (8)
N1—C1	1.497 (5)	C3—H3A	0.9900
N1—C4	1.504 (4)	C3—H3B	0.9900
N1—H1NA	0.883 (19)	C4—H4A	0.9900
N1—H1NB	0.89 (2)	C4—H4B	0.9900
C1—C2	1.486 (12)
Cl1^i—Sn1—Cl1	180.0	N1—C1—H1A	110.9
Cl1^i—Sn1—Cl2	90.439 (16)	C2—C1—H1B	110.9
Cl1—Sn1—Cl2	89.560 (16)	N1—C1—H1B	110.9
Cl1^i—Sn1—Cl2^i	89.561 (16)	H1A—C1—H1B	108.9
Cl1—Sn1—Cl2^i	90.440 (16)	C1—C2—C3	102.7 (7)
Cl2—Sn1—Cl2^i	180.000 (18)	C1—C2—H2A	111.2
Cl1^i—Sn1—Cl2^ii	89.561 (16)	C3—C2—H2A	111.2
Cl1—Sn1—Cl2^ii	90.440 (16)	C1—C2—H2B	111.2
Cl2—Sn1—Cl2^ii	88.151 (19)	C3—C2—H2B	111.2
Cl2^i—Sn1—Cl2^ii	91.849 (19)	H2A—C2—H2B	109.1
Cl1^i—Sn1—Cl2^iii	90.439 (16)	C4—C3—C2	101.7 (5)
Cl1—Sn1—Cl2^iii	89.560 (16)	C4—C3—H3A	111.4
Cl2—Sn1—Cl2^iii	91.849 (19)	C2—C3—H3A	111.4
Cl2^i—Sn1—Cl2^iii	88.151 (19)	C4—C3—H3B	111.4
Cl2^ii—Sn1—Cl2^iii	180.000 (13)	C2—C3—H3B	111.4
C1—N1—C4	108.1 (3)	H3A—C3—H3B	109.3
C1—N1—H1NA	112 (5)	N1—C4—C3	104.0 (5)
C4—N1—H1NA	118 (4)	N1—C4—H4A	111.0
C1—N1—H1NB	105 (5)	C3—C4—H4A	111.0
C4—N1—H1NB	102 (4)	N1—C4—H4B	111.0
H1NA—N1—H1NB	110 (4)	C3—C4—H4B	111.0
C2—C1—N1	104.5 (7)	H4A—C4—H4B	109.0
C2—C1—H1A	110.9
C4—N1—C1—C2	−14 (2)	C1—N1—C4—C3	−13 (2)
N1—C1—C2—C3	36 (2)	C2—C3—C4—N1	34.7 (13)
C1—C2—C3—C4	−43.9 (15)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1NA···Cl2	0.88 (5)	2.54 (5)	3.365 (2)	156 (5)
N1—H1NB···Cl2^iv	0.89 (4)	2.81 (6)	3.472 (2)	133 (5)
N1—H1NB···Cl2^v	0.89 (4)	2.77 (5)	3.365 (2)	126 (4)

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