The title compound, (C8H16N)2[PbI4], crystallizes as an inorganic-organic hybrid perovskite, adopting the unusual 2ap × 2ap superstructure. As such, the structure consists of two-dimensional sheets of corner-sharing PbI6 octahedra in the ab plane, separated by bilayers of 2-(1-cyclohexenyl)ethylammonium cations. The ethylammonium groups are not in the plane of the cyclohexenyl rings.
Supporting information
CCDC reference: 616101
PbI2 (0.101 g, 0.219 mmol) was dissolved in 47% HI (4 ml) in a sample vial. C6H9C2H4NH2 (0.055 g, 0.454 mmol) was added and the precipitate was dissolved with methanol (9 ml). Crystals where grown by slow evaporation over a period of a number of days. An orange single-crystal suitable for X-ray diffraction analysis was selected and studied. Analysis calculated for C16H32I4N2Pb: C 19.87, H 3.33, N 2.90%; found: C 19.81, H 3.19, N 3.00%
H atoms were refined in idealized positions in the riding-model approximation, with C—H = 0.95 Å (CH) and 0.99 Å (CH2), and N—H = 0.91 Å [Uiso(H) = 1.2Ueq(C) and 1.5Ueq(N)]. The highest residual peak is 1.96 Å from H1A.
Data collection: SMART-NT (Bruker, 1998); cell refinement: SMART-NT; data reduction: SAINT-Plus (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and DIAMOND (Brandenburg,
1999); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2003).
Poly[bis[2-(1-cyclohexenyl)ethylammonium] di-µ-iodo-diodoplumbate(II)]
top
Crystal data top
(C8H16N)2[PbI4] | Z = 4 |
Mr = 967.23 | F(000) = 1744 |
Triclinic, P1 | Dx = 2.485 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 12.2053 (11) Å | Cell parameters from 1009 reflections |
b = 12.3053 (11) Å | θ = 2.4–28.3° |
c = 18.3182 (17) Å | µ = 11.31 mm−1 |
α = 80.629 (6)° | T = 173 K |
β = 72.455 (6)° | Plate, orange |
γ = 89.961 (6)° | 0.48 × 0.44 × 0.04 mm |
V = 2584.8 (4) Å3 | |
Data collection top
Bruker SMART CCD area-detector diffractometer | 10208 reflections with I > 2σ(I) |
ϕ and ω scans | Rint = 0.075 |
Absorption correction: integration (XPREP; Bruker, 1999) | θmax = 28°, θmin = 1.7° |
Tmin = 0.03, Tmax = 0.570 | h = −16→16 |
42465 measured reflections | k = −16→16 |
12456 independent reflections | l = −23→24 |
Refinement top
Refinement on F2 | 298 restraints |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.035 | w = 1/[σ2(Fo2) + (0.0373P)2 + 9.0164P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.093 | (Δ/σ)max = 0.002 |
S = 1.05 | Δρmax = 1.26 e Å−3 |
12456 reflections | Δρmin = −3.13 e Å−3 |
415 parameters | |
Crystal data top
(C8H16N)2[PbI4] | γ = 89.961 (6)° |
Mr = 967.23 | V = 2584.8 (4) Å3 |
Triclinic, P1 | Z = 4 |
a = 12.2053 (11) Å | Mo Kα radiation |
b = 12.3053 (11) Å | µ = 11.31 mm−1 |
c = 18.3182 (17) Å | T = 173 K |
α = 80.629 (6)° | 0.48 × 0.44 × 0.04 mm |
β = 72.455 (6)° | |
Data collection top
Bruker SMART CCD area-detector diffractometer | 12456 independent reflections |
Absorption correction: integration (XPREP; Bruker, 1999) | 10208 reflections with I > 2σ(I) |
Tmin = 0.03, Tmax = 0.570 | Rint = 0.075 |
42465 measured reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.035 | 298 restraints |
wR(F2) = 0.093 | H-atom parameters constrained |
S = 1.05 | Δρmax = 1.26 e Å−3 |
12456 reflections | Δρmin = −3.13 e Å−3 |
415 parameters | |
Special details top
Experimental. Numerical integration absorption corrections based on indexed crystal faces were applied using the XPREP routine (Bruker, 1999) |
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. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
Pb1 | 0.744949 (17) | 0.742226 (16) | 0.011981 (13) | 0.01792 (6) | |
Pb2 | 0.754951 (17) | 0.247984 (15) | −0.011962 (13) | 0.01810 (6) | |
I1 | 0.66775 (4) | 0.70962 (3) | 0.18976 (2) | 0.02745 (9) | |
I2 | 0.82825 (3) | 0.77957 (3) | −0.18475 (2) | 0.02349 (9) | |
I3 | 0.67182 (3) | 0.18961 (3) | 0.18510 (2) | 0.02372 (9) | |
I4 | 0.83164 (4) | 0.30155 (3) | −0.18971 (2) | 0.02732 (9) | |
I5 | 1.00036 (3) | 0.81722 (3) | −0.00155 (2) | 0.02389 (9) | |
I6 | 0.68421 (3) | 0.99491 (3) | 0.00055 (3) | 0.02475 (9) | |
I7 | 0.50042 (3) | 0.68354 (3) | −0.00179 (2) | 0.02396 (9) | |
I8 | 0.81573 (3) | 0.49516 (3) | −0.00072 (3) | 0.02514 (9) | |
C1 | 0.6741 (6) | 1.0294 (5) | −0.3295 (4) | 0.0331 (13) | |
C2 | 0.6398 (7) | 0.9582 (7) | −0.3650 (5) | 0.0423 (15) | |
H2 | 0.5592 | 0.9458 | −0.3544 | 0.051* | |
C3 | 0.7187 (8) | 0.8946 (7) | −0.4214 (5) | 0.0528 (19) | |
H3D | 0.7213 | 0.9272 | −0.475 | 0.063* | |
H3E | 0.6879 | 0.8173 | −0.411 | 0.063* | |
C4 | 0.8404 (7) | 0.8963 (7) | −0.4144 (5) | 0.0497 (18) | |
H4D | 0.8419 | 0.8456 | −0.3669 | 0.06* | |
H4E | 0.8941 | 0.8702 | −0.4597 | 0.06* | |
C5 | 0.8793 (7) | 1.0116 (7) | −0.4108 (5) | 0.0428 (16) | |
H5A | 0.8796 | 1.0619 | −0.4589 | 0.051* | |
H5B | 0.9588 | 1.0111 | −0.4075 | 0.051* | |
C6 | 0.8001 (6) | 1.0537 (6) | −0.3407 (5) | 0.0350 (14) | |
H6A | 0.8187 | 1.0191 | −0.2934 | 0.042* | |
H6B | 0.8145 | 1.1344 | −0.3472 | 0.042* | |
C7 | 0.5893 (6) | 1.0898 (6) | −0.2736 (5) | 0.0404 (15) | |
H7A | 0.5107 | 1.0689 | −0.273 | 0.049* | |
H7B | 0.6029 | 1.1699 | −0.2935 | 0.049* | |
C8 | 0.5943 (6) | 1.0680 (5) | −0.1902 (5) | 0.0359 (14) | |
H8A | 0.6708 | 1.0937 | −0.1894 | 0.043* | |
H8B | 0.5354 | 1.1102 | −0.158 | 0.043* | |
C9 | 0.8241 (6) | 0.3701 (6) | 0.3286 (4) | 0.0342 (13) | |
C10 | 0.8592 (7) | 0.2804 (7) | 0.3655 (5) | 0.0424 (15) | |
H10 | 0.9395 | 0.2727 | 0.3556 | 0.051* | |
C11 | 0.7787 (8) | 0.1914 (7) | 0.4216 (5) | 0.0545 (19) | |
H11A | 0.7775 | 0.1973 | 0.4751 | 0.065* | |
H11B | 0.8079 | 0.1187 | 0.4109 | 0.065* | |
C12 | 0.6561 (8) | 0.1976 (7) | 0.4164 (6) | 0.0542 (19) | |
H12A | 0.6521 | 0.1689 | 0.3698 | 0.065* | |
H12B | 0.6027 | 0.1512 | 0.4628 | 0.065* | |
C13 | 0.6206 (7) | 0.3148 (7) | 0.4119 (5) | 0.0463 (17) | |
H13A | 0.6227 | 0.3424 | 0.4593 | 0.056* | |
H13B | 0.5406 | 0.3175 | 0.4097 | 0.056* | |
C14 | 0.6995 (6) | 0.3888 (6) | 0.3407 (5) | 0.0362 (14) | |
H14A | 0.6797 | 0.3758 | 0.2942 | 0.043* | |
H14B | 0.6857 | 0.4668 | 0.3462 | 0.043* | |
C15 | 0.9104 (7) | 0.4577 (6) | 0.2729 (5) | 0.0422 (15) | |
H15A | 0.8973 | 0.5282 | 0.2928 | 0.051* | |
H15B | 0.9888 | 0.4363 | 0.2723 | 0.051* | |
C16 | 0.9047 (6) | 0.4759 (5) | 0.1906 (5) | 0.0364 (14) | |
H16A | 0.828 | 0.5015 | 0.1902 | 0.044* | |
H16B | 0.9631 | 0.5342 | 0.1583 | 0.044* | |
C17 | 0.3190 (6) | 0.4525 (5) | 0.3309 (4) | 0.0314 (12) | |
C18 | 0.2055 (6) | 0.4314 (6) | 0.3569 (4) | 0.0349 (14) | |
H18 | 0.1761 | 0.3705 | 0.3413 | 0.042* | |
C19 | 0.1217 (7) | 0.4941 (6) | 0.4074 (5) | 0.0484 (18) | |
H19A | 0.0618 | 0.5169 | 0.3825 | 0.058* | |
H19B | 0.0835 | 0.4447 | 0.4571 | 0.058* | |
C20 | 0.1701 (8) | 0.5919 (9) | 0.4243 (8) | 0.095 (4) | |
H20A | 0.1399 | 0.6571 | 0.3988 | 0.114* | |
H20B | 0.1395 | 0.5907 | 0.481 | 0.114* | |
C21 | 0.2932 (7) | 0.6095 (10) | 0.4024 (8) | 0.088 (3) | |
H21A | 0.3134 | 0.5998 | 0.4514 | 0.105* | |
H21B | 0.3104 | 0.6882 | 0.3787 | 0.105* | |
C22 | 0.3738 (7) | 0.5479 (7) | 0.3513 (5) | 0.0467 (18) | |
H22A | 0.4318 | 0.5196 | 0.3766 | 0.056* | |
H22B | 0.4147 | 0.5985 | 0.3028 | 0.056* | |
C23 | 0.3994 (6) | 0.3841 (6) | 0.2772 (5) | 0.0368 (14) | |
H23A | 0.4644 | 0.3634 | 0.2975 | 0.044* | |
H23B | 0.3572 | 0.3153 | 0.2775 | 0.044* | |
C24 | 0.4467 (6) | 0.4444 (6) | 0.1942 (4) | 0.0356 (14) | |
H24A | 0.487 | 0.5145 | 0.1936 | 0.043* | |
H24B | 0.5033 | 0.3988 | 0.1633 | 0.043* | |
C25 | 0.8199 (6) | 0.8850 (5) | 0.3302 (4) | 0.0307 (12) | |
C26 | 0.8778 (8) | 0.7808 (7) | 0.3503 (5) | 0.0501 (19) | |
H26A | 0.9062 | 0.7462 | 0.3034 | 0.06* | |
H26B | 0.9452 | 0.8004 | 0.3658 | 0.06* | |
C27 | 0.8005 (9) | 0.6986 (7) | 0.4144 (7) | 0.067 (2) | |
H27A | 0.833 | 0.6251 | 0.4119 | 0.08* | |
H27B | 0.7996 | 0.7186 | 0.4648 | 0.08* | |
C28 | 0.6816 (10) | 0.6908 (8) | 0.4122 (7) | 0.069 (2) | |
H28A | 0.6353 | 0.6402 | 0.4591 | 0.083* | |
H28B | 0.6811 | 0.6581 | 0.3663 | 0.083* | |
C29 | 0.6254 (7) | 0.7994 (7) | 0.4083 (5) | 0.0472 (17) | |
H29A | 0.5954 | 0.817 | 0.4614 | 0.057* | |
H29B | 0.5595 | 0.7931 | 0.3881 | 0.057* | |
C30 | 0.7077 (6) | 0.8919 (6) | 0.3570 (4) | 0.0356 (14) | |
H30 | 0.6763 | 0.96 | 0.343 | 0.043* | |
C31 | 0.8977 (6) | 0.9809 (6) | 0.2782 (4) | 0.0338 (13) | |
H31A | 0.9623 | 0.9925 | 0.2987 | 0.041* | |
H31B | 0.8538 | 1.0486 | 0.2793 | 0.041* | |
C32 | 0.9458 (6) | 0.9625 (6) | 0.1947 (4) | 0.0356 (14) | |
H32A | 1.0008 | 1.0245 | 0.1642 | 0.043* | |
H32B | 0.9881 | 0.8938 | 0.1935 | 0.043* | |
N1 | 0.5739 (4) | 0.9479 (4) | −0.1566 (3) | 0.0271 (11) | |
H1A | 0.5789 | 0.9368 | −0.1074 | 0.041* | |
H1B | 0.6278 | 0.909 | −0.1864 | 0.041* | |
H1C | 0.5025 | 0.9248 | −0.1556 | 0.041* | |
N2 | 0.9258 (4) | 0.3723 (4) | 0.1563 (3) | 0.0271 (11) | |
H2A | 0.9202 | 0.3853 | 0.1073 | 0.041* | |
H2B | 0.8725 | 0.3184 | 0.1861 | 0.041* | |
H2C | 0.9975 | 0.3501 | 0.1548 | 0.041* | |
N3 | 0.3525 (5) | 0.4682 (4) | 0.1583 (3) | 0.0292 (11) | |
H3A | 0.3826 | 0.5062 | 0.1091 | 0.044* | |
H3B | 0.2999 | 0.5093 | 0.1871 | 0.044* | |
H3C | 0.3176 | 0.4037 | 0.1567 | 0.044* | |
N4 | 0.8526 (5) | 0.9542 (4) | 0.1587 (3) | 0.0296 (11) | |
H4A | 0.8835 | 0.9408 | 0.1094 | 0.044* | |
H4B | 0.8161 | 1.0186 | 0.1576 | 0.044* | |
H4C | 0.8013 | 0.898 | 0.1872 | 0.044* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Pb1 | 0.01506 (10) | 0.01716 (10) | 0.02336 (13) | 0.00111 (7) | −0.00807 (9) | −0.00440 (8) |
Pb2 | 0.01531 (10) | 0.01674 (10) | 0.02384 (13) | 0.00111 (7) | −0.00830 (9) | −0.00354 (8) |
I1 | 0.0297 (2) | 0.0283 (2) | 0.0233 (2) | −0.00233 (15) | −0.00697 (17) | −0.00360 (16) |
I2 | 0.02114 (18) | 0.02472 (18) | 0.0248 (2) | 0.00173 (14) | −0.00860 (16) | −0.00189 (15) |
I3 | 0.02104 (18) | 0.02674 (19) | 0.0251 (2) | 0.00054 (14) | −0.00833 (16) | −0.00677 (15) |
I4 | 0.0297 (2) | 0.02790 (19) | 0.0234 (2) | 0.00438 (15) | −0.00692 (17) | −0.00410 (16) |
I5 | 0.01334 (16) | 0.02837 (19) | 0.0326 (2) | 0.00201 (13) | −0.00954 (15) | −0.00774 (16) |
I6 | 0.02846 (19) | 0.01533 (16) | 0.0342 (2) | 0.00235 (14) | −0.01386 (17) | −0.00667 (15) |
I7 | 0.01341 (16) | 0.02687 (19) | 0.0325 (2) | 0.00049 (13) | −0.00931 (15) | −0.00326 (16) |
I8 | 0.02894 (19) | 0.01461 (16) | 0.0352 (2) | 0.00205 (14) | −0.01432 (17) | −0.00511 (15) |
C1 | 0.033 (3) | 0.031 (3) | 0.032 (3) | 0.000 (2) | −0.011 (2) | 0.005 (2) |
C2 | 0.042 (3) | 0.052 (4) | 0.034 (4) | −0.008 (3) | −0.016 (3) | 0.000 (3) |
C3 | 0.069 (4) | 0.050 (4) | 0.038 (5) | −0.011 (4) | −0.013 (4) | −0.009 (3) |
C4 | 0.060 (4) | 0.050 (4) | 0.032 (4) | 0.011 (3) | −0.001 (4) | −0.010 (3) |
C5 | 0.037 (3) | 0.054 (4) | 0.036 (4) | 0.006 (3) | −0.010 (3) | −0.006 (3) |
C6 | 0.032 (3) | 0.034 (3) | 0.037 (4) | 0.000 (3) | −0.011 (3) | −0.001 (3) |
C7 | 0.037 (3) | 0.038 (4) | 0.043 (4) | 0.007 (3) | −0.012 (3) | 0.002 (3) |
C8 | 0.036 (3) | 0.027 (3) | 0.042 (3) | 0.003 (3) | −0.007 (3) | −0.006 (3) |
C9 | 0.037 (3) | 0.041 (3) | 0.032 (3) | 0.004 (2) | −0.016 (3) | −0.016 (2) |
C10 | 0.039 (3) | 0.062 (4) | 0.033 (4) | 0.018 (3) | −0.019 (3) | −0.013 (3) |
C11 | 0.071 (4) | 0.052 (4) | 0.042 (5) | 0.021 (3) | −0.019 (4) | −0.006 (3) |
C12 | 0.060 (4) | 0.048 (3) | 0.045 (5) | −0.007 (3) | −0.006 (4) | 0.000 (3) |
C13 | 0.042 (3) | 0.057 (4) | 0.036 (4) | 0.005 (3) | −0.009 (3) | −0.005 (3) |
C14 | 0.038 (3) | 0.037 (3) | 0.037 (4) | 0.007 (2) | −0.014 (3) | −0.007 (3) |
C15 | 0.038 (3) | 0.046 (4) | 0.048 (4) | −0.003 (3) | −0.013 (3) | −0.023 (3) |
C16 | 0.034 (3) | 0.025 (3) | 0.047 (4) | −0.001 (3) | −0.008 (3) | −0.006 (3) |
C17 | 0.038 (3) | 0.026 (3) | 0.034 (3) | 0.001 (2) | −0.016 (2) | −0.003 (2) |
C18 | 0.040 (3) | 0.032 (3) | 0.034 (4) | −0.006 (2) | −0.012 (3) | −0.005 (3) |
C19 | 0.041 (3) | 0.054 (4) | 0.047 (5) | 0.004 (3) | −0.008 (3) | −0.012 (4) |
C20 | 0.077 (5) | 0.080 (6) | 0.118 (9) | −0.004 (5) | 0.012 (6) | −0.066 (6) |
C21 | 0.078 (5) | 0.084 (6) | 0.108 (8) | −0.016 (5) | −0.013 (6) | −0.069 (6) |
C22 | 0.047 (4) | 0.053 (4) | 0.045 (5) | −0.015 (3) | −0.015 (3) | −0.018 (3) |
C23 | 0.037 (3) | 0.038 (3) | 0.038 (3) | 0.007 (3) | −0.017 (3) | −0.006 (3) |
C24 | 0.029 (3) | 0.040 (4) | 0.038 (3) | 0.000 (3) | −0.010 (3) | −0.009 (3) |
C25 | 0.037 (3) | 0.032 (3) | 0.028 (3) | 0.007 (2) | −0.016 (2) | −0.009 (2) |
C26 | 0.056 (4) | 0.046 (4) | 0.042 (5) | 0.023 (3) | −0.012 (4) | 0.001 (3) |
C27 | 0.081 (5) | 0.039 (4) | 0.066 (6) | 0.019 (4) | −0.010 (5) | 0.008 (4) |
C28 | 0.086 (5) | 0.045 (4) | 0.060 (6) | −0.010 (4) | −0.009 (5) | 0.012 (4) |
C29 | 0.045 (4) | 0.055 (4) | 0.037 (4) | −0.007 (3) | −0.007 (3) | −0.004 (3) |
C30 | 0.038 (3) | 0.040 (3) | 0.027 (4) | 0.006 (2) | −0.006 (3) | −0.005 (3) |
C31 | 0.037 (3) | 0.034 (3) | 0.037 (3) | 0.000 (2) | −0.020 (3) | −0.008 (3) |
C32 | 0.028 (3) | 0.041 (4) | 0.038 (3) | 0.003 (3) | −0.012 (3) | −0.001 (3) |
N1 | 0.023 (2) | 0.028 (2) | 0.031 (3) | 0.000 (2) | −0.010 (2) | −0.006 (2) |
N2 | 0.022 (2) | 0.031 (3) | 0.030 (3) | 0.005 (2) | −0.011 (2) | −0.006 (2) |
N3 | 0.031 (3) | 0.027 (3) | 0.028 (3) | 0.003 (2) | −0.007 (2) | −0.005 (2) |
N4 | 0.034 (3) | 0.028 (3) | 0.027 (3) | −0.003 (2) | −0.009 (2) | −0.005 (2) |
Geometric parameters (Å, º) top
Pb1—I1 | 3.0626 (6) | C16—H16B | 0.99 |
Pb1—I7 | 3.1636 (5) | C17—C18 | 1.333 (10) |
Pb1—I5 | 3.1772 (5) | C17—C22 | 1.504 (9) |
Pb1—I6 | 3.1843 (5) | C17—C23 | 1.525 (10) |
Pb1—I8 | 3.1858 (5) | C18—C19 | 1.469 (7) |
Pb1—I2 | 3.3889 (6) | C18—H18 | 0.95 |
Pb2—I4 | 3.0622 (6) | C19—C20 | 1.459 (7) |
Pb2—I5i | 3.1626 (5) | C19—H19A | 0.99 |
Pb2—I7ii | 3.1750 (5) | C19—H19B | 0.99 |
Pb2—I8 | 3.1848 (5) | C20—C21 | 1.439 (7) |
Pb2—I6iii | 3.1856 (5) | C20—H20A | 0.99 |
Pb2—I3 | 3.3947 (6) | C20—H20B | 0.99 |
I5—Pb2i | 3.1626 (5) | C21—C22 | 1.447 (7) |
I6—Pb2iv | 3.1856 (5) | C21—H21A | 0.99 |
I7—Pb2ii | 3.1750 (5) | C21—H21B | 0.99 |
C1—C2 | 1.311 (10) | C22—H22A | 0.99 |
C1—C7 | 1.509 (10) | C22—H22B | 0.99 |
C1—C6 | 1.512 (9) | C23—C24 | 1.515 (10) |
C2—C3 | 1.506 (12) | C23—H23A | 0.99 |
C2—H2 | 0.95 | C23—H23B | 0.99 |
C3—C4 | 1.530 (12) | C24—N3 | 1.495 (9) |
C3—H3D | 0.99 | C24—H24A | 0.99 |
C3—H3E | 0.99 | C24—H24B | 0.99 |
C4—C5 | 1.514 (11) | C25—C30 | 1.317 (10) |
C4—H4D | 0.99 | C25—C26 | 1.510 (9) |
C4—H4E | 0.99 | C25—C31 | 1.514 (10) |
C5—C6 | 1.523 (10) | C26—C27 | 1.496 (12) |
C5—H5A | 0.99 | C26—H26A | 0.99 |
C5—H5B | 0.99 | C26—H26B | 0.99 |
C6—H6A | 0.99 | C27—C28 | 1.467 (15) |
C6—H6B | 0.99 | C27—H27A | 0.99 |
C7—C8 | 1.527 (11) | C27—H27B | 0.99 |
C7—H7A | 0.99 | C28—C29 | 1.502 (13) |
C7—H7B | 0.99 | C28—H28A | 0.99 |
C8—N1 | 1.496 (8) | C28—H28B | 0.99 |
C8—H8A | 0.99 | C29—C30 | 1.508 (10) |
C8—H8B | 0.99 | C29—H29A | 0.99 |
C9—C10 | 1.338 (10) | C29—H29B | 0.99 |
C9—C14 | 1.493 (10) | C30—H30 | 0.95 |
C9—C15 | 1.519 (11) | C31—C32 | 1.518 (10) |
C10—C11 | 1.498 (12) | C31—H31A | 0.99 |
C10—H10 | 0.95 | C31—H31B | 0.99 |
C11—C12 | 1.528 (13) | C32—N4 | 1.488 (8) |
C11—H11A | 0.99 | C32—H32A | 0.99 |
C11—H11B | 0.99 | C32—H32B | 0.99 |
C12—C13 | 1.502 (11) | N1—H1A | 0.91 |
C12—H12A | 0.99 | N1—H1B | 0.91 |
C12—H12B | 0.99 | N1—H1C | 0.91 |
C13—C14 | 1.521 (11) | N2—H2A | 0.91 |
C13—H13A | 0.99 | N2—H2B | 0.91 |
C13—H13B | 0.99 | N2—H2C | 0.91 |
C14—H14A | 0.99 | N3—H3A | 0.91 |
C14—H14B | 0.99 | N3—H3B | 0.91 |
C15—C16 | 1.509 (11) | N3—H3C | 0.91 |
C15—H15A | 0.99 | N4—H4A | 0.91 |
C15—H15B | 0.99 | N4—H4B | 0.91 |
C16—N2 | 1.500 (8) | N4—H4C | 0.91 |
C16—H16A | 0.99 | | |
| | | |
I1—Pb1—I7 | 95.586 (14) | N2—C16—H16A | 109.3 |
I1—Pb1—I5 | 92.827 (14) | C15—C16—H16A | 109.3 |
I7—Pb1—I5 | 171.227 (13) | N2—C16—H16B | 109.3 |
I1—Pb1—I6 | 91.405 (14) | C15—C16—H16B | 109.3 |
I7—Pb1—I6 | 89.114 (13) | H16A—C16—H16B | 108 |
I5—Pb1—I6 | 88.197 (12) | C18—C17—C22 | 121.3 (6) |
I1—Pb1—I8 | 96.074 (14) | C18—C17—C23 | 122.1 (6) |
I7—Pb1—I8 | 90.128 (12) | C22—C17—C23 | 116.6 (6) |
I5—Pb1—I8 | 91.451 (12) | C17—C18—C19 | 125.8 (6) |
I6—Pb1—I8 | 172.521 (14) | C17—C18—H18 | 117.1 |
I1—Pb1—I2 | 179.490 (12) | C19—C18—H18 | 117.1 |
I7—Pb1—I2 | 84.050 (13) | C20—C19—C18 | 114.8 (7) |
I5—Pb1—I2 | 87.520 (13) | C20—C19—H19A | 108.6 |
I6—Pb1—I2 | 88.233 (13) | C18—C19—H19A | 108.6 |
I8—Pb1—I2 | 84.288 (13) | C20—C19—H19B | 108.6 |
I4—Pb2—I5i | 95.620 (14) | C18—C19—H19B | 108.6 |
I4—Pb2—I7ii | 92.785 (14) | H19A—C19—H19B | 107.5 |
I5i—Pb2—I7ii | 171.223 (13) | C21—C20—C19 | 119.3 (8) |
I4—Pb2—I8 | 91.351 (14) | C21—C20—H20A | 107.5 |
I5i—Pb2—I8 | 89.044 (12) | C19—C20—H20A | 107.5 |
I7ii—Pb2—I8 | 88.230 (12) | C21—C20—H20B | 107.5 |
I4—Pb2—I6iii | 96.010 (14) | C19—C20—H20B | 107.5 |
I5i—Pb2—I6iii | 90.241 (12) | H20A—C20—H20B | 107 |
I7ii—Pb2—I6iii | 91.395 (13) | C20—C21—C22 | 124.0 (7) |
I8—Pb2—I6iii | 172.639 (14) | C20—C21—H21A | 106.3 |
I4—Pb2—I3 | 179.558 (12) | C22—C21—H21A | 106.3 |
I5i—Pb2—I3 | 84.052 (13) | C20—C21—H21B | 106.3 |
I7ii—Pb2—I3 | 87.530 (13) | C22—C21—H21B | 106.3 |
I8—Pb2—I3 | 88.348 (13) | H21A—C21—H21B | 106.4 |
I6iii—Pb2—I3 | 84.291 (13) | C21—C22—C17 | 114.0 (7) |
Pb2i—I5—Pb1 | 148.717 (15) | C21—C22—H22A | 108.8 |
Pb1—I6—Pb2iv | 150.927 (15) | C17—C22—H22A | 108.8 |
Pb1—I7—Pb2ii | 148.632 (15) | C21—C22—H22B | 108.8 |
Pb2—I8—Pb1 | 150.948 (15) | C17—C22—H22B | 108.8 |
C2—C1—C7 | 121.5 (7) | H22A—C22—H22B | 107.7 |
C2—C1—C6 | 122.0 (7) | C24—C23—C17 | 113.1 (6) |
C7—C1—C6 | 116.5 (6) | C24—C23—H23A | 109 |
C1—C2—C3 | 124.8 (7) | C17—C23—H23A | 109 |
C1—C2—H2 | 117.6 | C24—C23—H23B | 109 |
C3—C2—H2 | 117.6 | C17—C23—H23B | 109 |
C2—C3—C4 | 111.3 (7) | H23A—C23—H23B | 107.8 |
C2—C3—H3D | 109.4 | N3—C24—C23 | 111.1 (6) |
C4—C3—H3D | 109.4 | N3—C24—H24A | 109.4 |
C2—C3—H3E | 109.4 | C23—C24—H24A | 109.4 |
C4—C3—H3E | 109.4 | N3—C24—H24B | 109.4 |
H3D—C3—H3E | 108 | C23—C24—H24B | 109.4 |
C5—C4—C3 | 110.8 (7) | H24A—C24—H24B | 108 |
C5—C4—H4D | 109.5 | C30—C25—C26 | 121.5 (7) |
C3—C4—H4D | 109.5 | C30—C25—C31 | 121.9 (6) |
C5—C4—H4E | 109.5 | C26—C25—C31 | 116.6 (6) |
C3—C4—H4E | 109.5 | C27—C26—C25 | 113.6 (7) |
H4D—C4—H4E | 108.1 | C27—C26—H26A | 108.9 |
C4—C5—C6 | 111.0 (6) | C25—C26—H26A | 108.9 |
C4—C5—H5A | 109.4 | C27—C26—H26B | 108.9 |
C6—C5—H5A | 109.4 | C25—C26—H26B | 108.9 |
C4—C5—H5B | 109.4 | H26A—C26—H26B | 107.7 |
C6—C5—H5B | 109.4 | C28—C27—C26 | 114.3 (9) |
H5A—C5—H5B | 108 | C28—C27—H27A | 108.7 |
C1—C6—C5 | 112.9 (6) | C26—C27—H27A | 108.7 |
C1—C6—H6A | 109 | C28—C27—H27B | 108.7 |
C5—C6—H6A | 109 | C26—C27—H27B | 108.7 |
C1—C6—H6B | 109 | H27A—C27—H27B | 107.6 |
C5—C6—H6B | 109 | C27—C28—C29 | 114.1 (8) |
H6A—C6—H6B | 107.8 | C27—C28—H28A | 108.7 |
C1—C7—C8 | 115.2 (6) | C29—C28—H28A | 108.7 |
C1—C7—H7A | 108.5 | C27—C28—H28B | 108.7 |
C8—C7—H7A | 108.5 | C29—C28—H28B | 108.7 |
C1—C7—H7B | 108.5 | H28A—C28—H28B | 107.6 |
C8—C7—H7B | 108.5 | C28—C29—C30 | 112.2 (7) |
H7A—C7—H7B | 107.5 | C28—C29—H29A | 109.2 |
N1—C8—C7 | 111.1 (6) | C30—C29—H29A | 109.2 |
N1—C8—H8A | 109.4 | C28—C29—H29B | 109.2 |
C7—C8—H8A | 109.4 | C30—C29—H29B | 109.2 |
N1—C8—H8B | 109.4 | H29A—C29—H29B | 107.9 |
C7—C8—H8B | 109.4 | C25—C30—C29 | 124.6 (7) |
H8A—C8—H8B | 108 | C25—C30—H30 | 117.7 |
C10—C9—C14 | 121.7 (7) | C29—C30—H30 | 117.7 |
C10—C9—C15 | 120.9 (7) | C25—C31—C32 | 112.6 (6) |
C14—C9—C15 | 117.3 (7) | C25—C31—H31A | 109.1 |
C9—C10—C11 | 123.6 (7) | C32—C31—H31A | 109.1 |
C9—C10—H10 | 118.2 | C25—C31—H31B | 109.1 |
C11—C10—H10 | 118.2 | C32—C31—H31B | 109.1 |
C10—C11—C12 | 112.7 (7) | H31A—C31—H31B | 107.8 |
C10—C11—H11A | 109 | N4—C32—C31 | 111.3 (6) |
C12—C11—H11A | 109 | N4—C32—H32A | 109.4 |
C10—C11—H11B | 109 | C31—C32—H32A | 109.4 |
C12—C11—H11B | 109 | N4—C32—H32B | 109.4 |
H11A—C11—H11B | 107.8 | C31—C32—H32B | 109.4 |
C13—C12—C11 | 110.2 (7) | H32A—C32—H32B | 108 |
C13—C12—H12A | 109.6 | C8—N1—H1A | 109.5 |
C11—C12—H12A | 109.6 | C8—N1—H1B | 109.5 |
C13—C12—H12B | 109.6 | H1A—N1—H1B | 109.5 |
C11—C12—H12B | 109.6 | C8—N1—H1C | 109.5 |
H12A—C12—H12B | 108.1 | H1A—N1—H1C | 109.5 |
C12—C13—C14 | 111.4 (7) | H1B—N1—H1C | 109.5 |
C12—C13—H13A | 109.3 | C16—N2—H2A | 109.5 |
C14—C13—H13A | 109.3 | C16—N2—H2B | 109.5 |
C12—C13—H13B | 109.3 | H2A—N2—H2B | 109.5 |
C14—C13—H13B | 109.3 | C16—N2—H2C | 109.5 |
H13A—C13—H13B | 108 | H2A—N2—H2C | 109.5 |
C9—C14—C13 | 113.3 (6) | H2B—N2—H2C | 109.5 |
C9—C14—H14A | 108.9 | C24—N3—H3A | 109.5 |
C13—C14—H14A | 108.9 | C24—N3—H3B | 109.5 |
C9—C14—H14B | 108.9 | H3A—N3—H3B | 109.5 |
C13—C14—H14B | 108.9 | C24—N3—H3C | 109.5 |
H14A—C14—H14B | 107.7 | H3A—N3—H3C | 109.5 |
C16—C15—C9 | 114.5 (6) | H3B—N3—H3C | 109.5 |
C16—C15—H15A | 108.6 | C32—N4—H4A | 109.5 |
C9—C15—H15A | 108.6 | C32—N4—H4B | 109.5 |
C16—C15—H15B | 108.6 | H4A—N4—H4B | 109.5 |
C9—C15—H15B | 108.6 | C32—N4—H4C | 109.5 |
H15A—C15—H15B | 107.6 | H4A—N4—H4C | 109.5 |
N2—C16—C15 | 111.5 (6) | H4B—N4—H4C | 109.5 |
| | | |
I1—Pb1—I5—Pb2i | 76.86 (3) | C15—C9—C10—C11 | 179.6 (7) |
I6—Pb1—I5—Pb2i | 168.17 (3) | C9—C10—C11—C12 | 15.0 (12) |
I8—Pb1—I5—Pb2i | −19.30 (3) | C10—C11—C12—C13 | −44.3 (10) |
I2—Pb1—I5—Pb2i | −103.52 (3) | C11—C12—C13—C14 | 60.2 (10) |
I1—Pb1—I6—Pb2iv | 90.28 (3) | C10—C9—C14—C13 | 15.0 (10) |
I7—Pb1—I6—Pb2iv | −174.15 (3) | C15—C9—C14—C13 | −164.6 (6) |
I5—Pb1—I6—Pb2iv | −2.50 (3) | C12—C13—C14—C9 | −45.2 (9) |
I2—Pb1—I6—Pb2iv | −90.07 (3) | C10—C9—C15—C16 | 119.6 (8) |
I1—Pb1—I7—Pb2ii | 72.36 (3) | C14—C9—C15—C16 | −60.8 (8) |
I6—Pb1—I7—Pb2ii | −18.96 (3) | C9—C15—C16—N2 | −59.3 (8) |
I8—Pb1—I7—Pb2ii | 168.48 (3) | C22—C17—C18—C19 | −0.8 (12) |
I2—Pb1—I7—Pb2ii | −107.28 (3) | C23—C17—C18—C19 | −178.8 (7) |
I4—Pb2—I8—Pb1 | 90.40 (3) | C17—C18—C19—C20 | 4.8 (14) |
I5i—Pb2—I8—Pb1 | −174.00 (3) | C18—C19—C20—C21 | −10.0 (18) |
I7ii—Pb2—I8—Pb1 | −2.35 (3) | C19—C20—C21—C22 | 12 (2) |
I3—Pb2—I8—Pb1 | −89.93 (3) | C20—C21—C22—C17 | −7.8 (19) |
I1—Pb1—I8—Pb2 | 91.41 (3) | C18—C17—C22—C21 | 1.9 (13) |
I7—Pb1—I8—Pb2 | −4.22 (3) | C23—C17—C22—C21 | 180.0 (9) |
I5—Pb1—I8—Pb2 | −175.59 (3) | C18—C17—C23—C24 | 106.8 (8) |
I2—Pb1—I8—Pb2 | −88.23 (3) | C22—C17—C23—C24 | −71.3 (8) |
C7—C1—C2—C3 | −180.0 (7) | C17—C23—C24—N3 | −64.0 (8) |
C6—C1—C2—C3 | −1.3 (12) | C30—C25—C26—C27 | −11.8 (12) |
C1—C2—C3—C4 | 16.9 (12) | C31—C25—C26—C27 | 167.8 (8) |
C2—C3—C4—C5 | −45.6 (10) | C25—C26—C27—C28 | 38.5 (12) |
C3—C4—C5—C6 | 60.4 (9) | C26—C27—C28—C29 | −53.1 (13) |
C2—C1—C6—C5 | 14.9 (10) | C27—C28—C29—C30 | 38.5 (12) |
C7—C1—C6—C5 | −166.4 (6) | C26—C25—C30—C29 | −1.0 (12) |
C4—C5—C6—C1 | −44.0 (9) | C31—C25—C30—C29 | 179.4 (7) |
C2—C1—C7—C8 | 118.4 (8) | C28—C29—C30—C25 | −12.1 (12) |
C6—C1—C7—C8 | −60.3 (9) | C30—C25—C31—C32 | −108.2 (8) |
C1—C7—C8—N1 | −58.5 (8) | C26—C25—C31—C32 | 72.2 (8) |
C14—C9—C10—C11 | 0.0 (12) | C25—C31—C32—N4 | 63.6 (8) |
Symmetry codes: (i) −x+2, −y+1, −z; (ii) −x+1, −y+1, −z; (iii) x, y−1, z; (iv) x, y+1, z. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···I6 | 0.91 | 2.84 | 3.649 (5) | 149 |
N1—H1B···I2 | 0.91 | 2.92 | 3.683 (5) | 142 |
N1—H1C···I3ii | 0.91 | 2.78 | 3.656 (5) | 161 |
N2—H2A···I8 | 0.91 | 2.83 | 3.644 (5) | 150 |
N2—H2B···I3 | 0.91 | 2.93 | 3.685 (5) | 142 |
N2—H2C···I2i | 0.91 | 2.79 | 3.659 (5) | 160 |
N3—H3A···I7 | 0.91 | 2.78 | 3.628 (6) | 155 |
N3—H3B···I4ii | 0.91 | 2.83 | 3.626 (5) | 148 |
N3—H3C···I2ii | 0.91 | 2.76 | 3.644 (5) | 166 |
N4—H4A···I5 | 0.91 | 2.78 | 3.623 (6) | 154 |
N4—H4B···I3iv | 0.91 | 2.75 | 3.647 (6) | 167 |
N4—H4C···I1 | 0.91 | 2.82 | 3.626 (5) | 148 |
Symmetry codes: (i) −x+2, −y+1, −z; (ii) −x+1, −y+1, −z; (iv) x, y+1, z. |
Experimental details
Crystal data |
Chemical formula | (C8H16N)2[PbI4] |
Mr | 967.23 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 173 |
a, b, c (Å) | 12.2053 (11), 12.3053 (11), 18.3182 (17) |
α, β, γ (°) | 80.629 (6), 72.455 (6), 89.961 (6) |
V (Å3) | 2584.8 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 11.31 |
Crystal size (mm) | 0.48 × 0.44 × 0.04 |
|
Data collection |
Diffractometer | Bruker SMART CCD area-detector diffractometer |
Absorption correction | Integration (XPREP; Bruker, 1999) |
Tmin, Tmax | 0.03, 0.570 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 42465, 12456, 10208 |
Rint | 0.075 |
(sin θ/λ)max (Å−1) | 0.661 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.035, 0.093, 1.05 |
No. of reflections | 12456 |
No. of parameters | 415 |
No. of restraints | 298 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 1.26, −3.13 |
Selected bond lengths (Å) topPb1—I1 | 3.0626 (6) | Pb2—I4 | 3.0622 (6) |
Pb1—I7 | 3.1636 (5) | Pb2—I5i | 3.1626 (5) |
Pb1—I5 | 3.1772 (5) | Pb2—I7ii | 3.1750 (5) |
Pb1—I6 | 3.1843 (5) | Pb2—I8 | 3.1848 (5) |
Pb1—I8 | 3.1858 (5) | Pb2—I6iii | 3.1856 (5) |
Pb1—I2 | 3.3889 (6) | Pb2—I3 | 3.3947 (6) |
Symmetry codes: (i) −x+2, −y+1, −z; (ii) −x+1, −y+1, −z; (iii) x, y−1, z. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···I6 | 0.91 | 2.84 | 3.649 (5) | 149 |
N1—H1B···I2 | 0.91 | 2.92 | 3.683 (5) | 142 |
N1—H1C···I3ii | 0.91 | 2.78 | 3.656 (5) | 161 |
N2—H2A···I8 | 0.91 | 2.83 | 3.644 (5) | 150 |
N2—H2B···I3 | 0.91 | 2.93 | 3.685 (5) | 142 |
N2—H2C···I2i | 0.91 | 2.79 | 3.659 (5) | 160 |
N3—H3A···I7 | 0.91 | 2.78 | 3.628 (6) | 155 |
N3—H3B···I4ii | 0.91 | 2.83 | 3.626 (5) | 148 |
N3—H3C···I2ii | 0.91 | 2.76 | 3.644 (5) | 166 |
N4—H4A···I5 | 0.91 | 2.78 | 3.623 (6) | 154 |
N4—H4B···I3iv | 0.91 | 2.75 | 3.647 (6) | 167 |
N4—H4C···I1 | 0.91 | 2.82 | 3.626 (5) | 148 |
Symmetry codes: (i) −x+2, −y+1, −z; (ii) −x+1, −y+1, −z; (iv) x, y+1, z. |
The hybrid perovskites (C6H5C2H4NH3)2[PbX4] (X = Cl, Br and I) have been extensively investigated for their photoluminescence, electroluminescence and nonlinear optical properties (Mitzi, 1999a, and references therein). The hybrid perovskites are natural quantum-well structures as they consist of inorganic semiconducting layers of [MX4]2− perovskite sheets and organic ammonium cation (R—NH3)+ bilayers. Highly efficient electroluminesence has been found in the related materials (C6H5C4H8NH3)2[PbI4] and (C6H9C2H4NH3)2[PbI4] (Hattori et al., 1996). The latter and title compound, (I), which contains a six-membered ring with a C═ C bond, showed high luminescence, exceeding 4000 cd m−2. The reason for the high electroluminescence observed is the nature of the organic carrier transport material, in this case the C6H9C2H4NH3+ cation (Hattori et al., 1996). In this study, we present the detailed crystal structure of the hybrid perovskite (I) (Fig. 1).
Fig. 2 clearly underlines a bidimensional arrangement in which two layers of non-interdigitated 2-(1-cyclohexenyl)ethylammonium ions are embedded between two consecutive inorganic PbI6 sheets, forming an alternated inorganic–organic layered structure. The Pb atoms are aligned from layer to layer, resulting in an eclipsed arrangement of adjacent layers. In the direction perpendicular to the layers, the crystal cohesion is achieved on one end of the organic molecules by N—H···I hydrogen bridges, related to the NH3 polar groups. There are van der Waals forces between molecules [the nearest neighbour distance is 3.792 (18) Å]. In the direction parallel to the layers, the cohesion is archieved by strong ionic bonds between equatorial I and Pb atoms, giving the classical perovskite structural arrangement. An interesting feature of this hybrid perovskite is that the triclinic unit-cell dimensions parallel to the perovskite layers are twice the simple cubic perovskite lattice parameter of (CH3NH3)[PbI3] [ap = 6.3285 (4) Å; Mitzi, 1999b]. Most layered inorganic–organic hybrid perovskites show the 21/2ap × 21/2ap superstrucure, not the unusual 2ap × 2ap structure observed here (Mitzi, 1999b).
The inorganic layer is built up from characteristic corner-sharing PbI6 octahedra. The asymmetric unit consists of Pb atoms, Pb1 and Pb2, on general positions and eight I atoms, viz. atoms I1–I4 occupying the axial positions and I5–I8 occupying the equatorial positions in the octahedra. The four equatorial I atoms are corner-shared by neighbouring octahedra. As shown in the projection perpendicular to the layers, along the c axis, the PbI6 octahedra are rotated relative to each other (Fig. 3). The degree of rotation ranges from 148.632 (15) to 150.948 (15)° as there are four different bridging I atoms. Furthermore, the perovskite layers are corrugated. The tilt angles are 2.462° for Pb1 and 2.543° for Pb2. The coordination geometry around the Pb atoms shows axial compression of the octahedral geometry, with the bridging distances longer than the axial distances. The bridging lead–iodine bond distances are in a narrow range for both Pb1 and Pb2 [3.1626 (5)–3.1858 (5) Å; Table 1]. The longest bond distances are to the axial atoms I2 and I3 [3.3889 (6) and 3.3947 (6) Å, respectively], whereas the shortest distances are to the I atoms trans to them, viz. I1 [3.0626 (6) Å] and I4 [3.0622 (6) Å]. The size of the parallelograms that make up the voids depends on which bridging iodides are used. There are four unique voids and the edge lengths range from 4.427 (12) to 4.556 (12) Å. The bond angles between cis- and trans-related I atoms within the octahedra all deviate from ideality. The cis angles range from 84.050 (13) to 96.074 (16)°. The trans angles between the bridging iodides deviate more from 180° [171.223(13)–172.639 (14)°] than those between the axial halides [179.490 (12) and 179.558 (12)°].
There are four unique 2-(1-cyclohexenyl)ethylammonium molecules in the asymmetric unit and their atomic numbering scheme is shown in Fig. 1. A l l four amine groups are well ordered between the layers; these groups are labeled cat1 (containing atom N1), cat2 (N2), cat3 (N3) and cat4 (N4). Three of the 1-cyclohexenyl rings are not planar. The r.m.s. deviation from the planes is 0.3041 (1) Å for cat1, 0.3095 (1) Å for cat2, 0.2591 (1) Å for cat3 and the least for cat4 [0.0586 (1) Å]. When viewing the cations perpendicular to the 1-cyclohexenyl rings, with the ethylammonium groups pointing towards you, they are bent towards the right for cat1, cat2 and cat4, and to the left for cat3. The direction is always to the side with the double bond. Futhermore, the terminal ethylammonium C and N atoms are not in the plane of the ring but are in a J-shaped conformation, similiar to the phenylethylammonium molecules in (C6H5C2H4NH3)2[PbCl4] (Mitzi, 1999a). Subsequently, the 1-cyclohexenyl rings are slanted towards the layers (33.916, 35.035, 37.179 and 37.994°, respectively, for cat1 to cat4).
The hydrogen bridges between the organic and inorganic entities adopt the terminal configuration for all four unique ammonium groups, i.e. two H atoms bond to axial I atoms and the third H atom to a bridging I atom (see Fig. 4). The H···A distances to the terminal halides range from 2.75 to 2.93 Å and to the bridging halides from 2.78 to 2.84 Å.