CH₃NH₃PbI₃: precise structural consequences of water absorption at ambient conditions

The crystal structure of the pristine (I) and aged (II) crystals of CH₃NH₃PbI₃ (hereafter MAPbI₃) hybrid organic–inorganic lead iodide has been studied at 293 K with high-precision single-crystal X-ray diffraction using a synchrotron light source. We show that (I) and (II) are characterized by an identical tetragonal unit cell but different space groups: I422 for (I) and P4₂2₁2 for (II). Both space groups are subgroups of I4/mcm, which is widely used for MAPbI₃. The main difference between (I) and (II) comes from the difference in hydrogen bonds between the MA⁺ cation and the PbI₃ framework which is the direct consequence of H₂O insertion in the aged crystal (II).

Computing details

For both compounds, data collection: CrysAlis PRO, Agilent Technologies, Version 1.171.37.35 (release 13-08-2014 CrysAlis171 .NET) (compiled Aug 13 2014,18:06:01); cell refinement: CrysAlis PRO, Agilent Technologies, Version 1.171.37.35 (release 13-08-2014 CrysAlis171 .NET) (compiled Aug 13 2014,18:06:01); data reduction: CrysAlis PRO, Agilent Technologies, Version 1.171.37.35 (release 13-08-2014 CrysAlis171 .NET) (compiled Aug 13 2014,18:06:01); program(s) used to solve structure: Palatinus L. & Chapuis G. (2007). J. Appl. Cryst. 40, 786-790; program(s) used to refine structure: Petricek, V., Dusek, M. & Palatinus L. (2014). Z. Kristallogr. 229 (5), 345-352.

(I)

Crystal data

I3Pb·CH6N	Dx = 4.108 Mg m^−3
Mr = 619.97	Synchrotron radiation, λ = 0.68362 Å
Tetragonal, I422	Cell parameters from 4261 reflections
Hall symbol: I 4 2	θ = 2.7–31.3°
a = 8.88375 (18) Å	µ = 23.28 mm^−1
c = 12.7010 (3) Å	T = 293 K
V = 1002.38 (5) Å^3	Irregular, dark grey
Z = 4	0.0025 × 0.0020 × 0.0015 mm
F(000) = 1040

Data collection

Dectris-CrysAlisPro-abstract goniometer imported dectris images diffractometer	721 reflections with I > 3σ(I)
Radiation source: synchrotron	Rint = 0.029
Synchrotron monochromator	θmax = 31.3°, θmin = 2.7°
Absorption correction: empirical (using intensity measurements) CrysAlisPro, Agilent Technologies, Version 1.171.37.35 (release 13-08-2014 CrysAlis171 .NET) (compiled Aug 13 2014,18:06:01) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.	h = −13→13
Tmin = 0.582, Tmax = 1.000	k = −13→13
4261 measured reflections	l = −13→13
773 independent reflections

Refinement

Refinement on F	Weighting scheme based on measured s.u.'s w = 1/(σ^2(F) + 0.0001F^2)
R[F^2 > 2σ(F^2)] = 0.012	(Δ/σ)max = 0.045
wR(F^2) = 0.015	Δρmax = 0.40 e Å^−3
S = 1.19	Δρmin = −0.36 e Å^−3
773 reflections	Extinction correction: B-C type 1 Gaussian isotropic (Becker & Coppens, 1974)
67 parameters	Extinction coefficient: 394E1 (9)
1 restraint	Absolute structure: 305 of Friedel pairs used in the refinement
31 constraints	Absolute structure parameter: 0.25 (13)
H-atom parameters constrained

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

	x	y	z	Uiso*/Ueq	Occ. (<1)
Pb1	1	1	0.74980 (5)	0.0374 (3)
I1_1	1	1	0.5	0.0764 (7)
I1_2	1	1	1	0.1027 (12)
I2	0.28604 (17)	0.78604 (17)	0.75	0.0873 (4)
C	1.0436 (15)	0.4947 (16)	0.5240 (14)	0.066 (6)*	0.25
N	0.934 (3)	0.574 (3)	0.4677 (11)	0.086 (3)*	0.25
H1n	0.850381	0.603186	0.516058	0.1031*	0.25
H2n	0.894125	0.509388	0.4098	0.1031*	0.25
H3n	0.980379	0.667029	0.43688	0.1031*	0.25
H1c	1.030773	0.384359	0.511218	0.0791*	0.25
H2c	1.032076	0.51604	0.600924	0.0791*	0.25
H3c	1.14599	0.526734	0.500292	0.0791*	0.25

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Pb1	0.0369 (3)	0.0369 (3)	0.0385 (6)	0	0	0
I1_1	0.0951 (12)	0.0951 (12)	0.0389 (15)	0	0	0
I1_2	0.142 (2)	0.142 (2)	0.0233 (13)	0	0	0
I2	0.0711 (5)	0.0711 (5)	0.1198 (10)	0.0413 (4)	−0.0037 (5)	0.0037 (5)

Geometric parameters (Å, º)

Pb1—I1_1	3.1727 (7)	Pb1—I2^iii	3.1733 (15)
Pb1—I1_2	3.1777 (7)	Pb1—I2^iv	3.1733 (15)
Pb1—I2^i	3.1733 (15)	C—N	1.40 (3)
Pb1—I2^ii	3.1733 (15)
I1_1—Pb1—I1_2	180.0 (5)	I2^i—Pb1—I2^ii	179.91 (2)
I1_1—Pb1—I2^i	90.045 (12)	I2^i—Pb1—I2^iii	90.00 (4)
I1_1—Pb1—I2^ii	90.045 (12)	I2^i—Pb1—I2^iv	90.00 (4)
I1_1—Pb1—I2^iii	90.045 (12)	I2^ii—Pb1—I2^iii	90.00 (4)
I1_1—Pb1—I2^iv	90.045 (12)	I2^ii—Pb1—I2^iv	90.00 (4)
I1_2—Pb1—I2^i	89.955 (12)	I2^iii—Pb1—I2^iv	179.91 (2)
I1_2—Pb1—I2^ii	89.955 (12)	Pb1—I1_1—Pb1^v	180.0 (5)
I1_2—Pb1—I2^iii	89.955 (12)	Pb1—I1_2—Pb1^vi	180.0 (5)
I1_2—Pb1—I2^iv	89.955 (12)	Pb1^vii—I2—Pb1^viii	163.59 (5)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N—H1n···I2^iv	1.00	3.18	4.017 (17)	141.93
N—H2n···I2^ix	1.00	3.00	3.99 (2)	173.69
N—H3n···I1_1	1.00	3.07	3.85 (3)	135.68
N—H3n···I2^x	1.00	3.18	3.92 (2)	131.83

Symmetry codes: (iv) y, −x+1, z; (ix) x+1/2, y−1/2, z−1/2; (x) −x+3/2, −y+3/2, z−1/2.

(II)

Crystal data

I2.982Pb·0.925(CH6N)·0.088(O)	Dx = 4.085 Mg m^−3
Mr = 616.41	Synchrotron radiation, λ = 0.68362 Å
Tetragonal, P42212	Cell parameters from 17735 reflections
Hall symbol: P 4n 2n	θ = 2.7–31.6°
a = 8.8829 (3) Å	µ = 23.23 mm^−1
c = 12.7008 (4) Å	T = 293 K
V = 1002.17 (7) Å^3	Irregular, black
Z = 4	0.0025 × 0.0020 × 0.0015 mm
F(000) = 1032.8

Data collection

Dectris-CrysAlisPro-abstract goniometer imported dectris images diffractometer	4191 independent reflections
Radiation source: synchrotron	1704 reflections with I > 3σ(I)
Synchrotron monochromator	Rint = 0.071
ω scans	θmax = 31.6°, θmin = 2.7°
Absorption correction: empirical (using intensity measurements) CrysAlisPro, Agilent Technologies, Version 1.171.37.35 (release 13-08-2014 CrysAlis171 .NET) (compiled Aug 13 2014,18:06:01) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.	h = −12→12
Tmin = 0.399, Tmax = 1.000	k = −13→13
17735 measured reflections	l = −18→18

Refinement

Refinement on F	Weighting scheme based on measured s.u.'s w = 1/(σ^2(F) + 0.0001F^2)
R[F^2 > 2σ(F^2)] = 0.041	(Δ/σ)max = 0.049
wR(F^2) = 0.068	Δρmax = 0.66 e Å^−3
S = 1.52	Δρmin = −0.88 e Å^−3
4191 reflections	Extinction correction: B-C type 1 Gaussian isotropic (Becker & Coppens, 1974)
195 parameters	Extinction coefficient: 19E1 (5)
2 restraints	Absolute structure: 1031 of Friedel pairs used in the refinement
14 constraints	Absolute structure parameter: 0.09 (5)
H-atom parameters constrained

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

	x	y	z	Uiso*/Ueq	Occ. (<1)
Pb1	0	0	0.7490 (6)	0.050 (2)
I1_1	0	0	0.5	0.111 (5)	0.96 (2)
I1_2	0	0	0	0.092 (4)
I2	0.2838 (4)	0.7681 (4)	0.7494 (3)	0.122 (2)
C1	−0.033 (5)	0.497 (6)	0.559 (3)	0.053 (10)*	0.167 (12)
C2	0.032 (5)	0.504 (6)	0.472 (3)	0.045 (9)*	0.295 (12)
N1	−0.085 (5)	0.568 (5)	0.467 (3)	0.041 (9)*	0.167 (12)
N2	−0.080 (4)	0.442 (5)	0.536 (3)	0.081 (12)*	0.295 (12)
H1n1	−0.192701	0.598638	0.477015	0.0497*	0.167 (12)
H1n2	−0.18101	0.479706	0.513253	0.0965*	0.295 (12)
H2n1	−0.022609	0.659276	0.452915	0.0497*	0.167 (12)
H2n2	−0.077722	0.329594	0.530291	0.0965*	0.295 (12)
H3n1	−0.077635	0.497049	0.406259	0.0497*	0.167 (12)
H3n2	−0.062261	0.471582	0.611239	0.0965*	0.295 (12)
O1	−0.5	1	0.811 (5)	0.010 (5)*	0.088 (18)
H1c1	0.079087	0.492789	0.557428	0.0633*	0.167 (12)
H2c1	−0.074537	0.391996	0.56162	0.0633*	0.167 (12)
H3c1	−0.067721	0.554366	0.621724	0.0633*	0.167 (12)
H1c2	0.120523	0.434809	0.470133	0.0545*	0.295 (12)
H2c2	0.063608	0.603647	0.501799	0.0545*	0.295 (12)
H3c2	−0.008307	0.518531	0.399536	0.0545*	0.295 (12)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Pb1	0.070 (4)	0.053 (3)	0.026 (4)	0.0009 (4)	0	0
I1_1	0.164 (11)	0.164 (11)	0.004 (2)	−0.028 (4)	0	0
I1_2	0.137 (9)	0.137 (9)	0.003 (2)	0.000 (3)	0	0
I2	0.066 (3)	0.150 (4)	0.149 (5)	0.043 (3)	0.022 (3)	−0.033 (3)

Geometric parameters (Å, º)

Pb1—I1_1	3.162 (7)	C1—N1	1.40 (6)
Pb1—I1_2^i	3.188 (7)	C1—O1^vii	1.68 (8)
Pb1—I2^ii	3.255 (3)	C2—N2	1.40 (6)
Pb1—I2^iii	3.255 (3)	C2—O1^vii	2.76 (8)
Pb1—I2^iv	3.060 (3)	N1—O1^vii	2.97 (8)
Pb1—I2^v	3.060 (3)	N2—O1^vii	2.12 (7)
I2—O1^vi	2.924 (19)
I1_1—Pb1—I1_2^i	180.0 (5)	I2^ii—Pb1—I2^iv	90.37 (9)
I1_1—Pb1—I2^ii	90.10 (14)	I2^ii—Pb1—I2^v	89.63 (9)
I1_1—Pb1—I2^iii	90.10 (14)	I2^iii—Pb1—I2^iv	89.63 (9)
I1_1—Pb1—I2^iv	90.37 (15)	I2^iii—Pb1—I2^v	90.37 (9)
I1_1—Pb1—I2^v	90.37 (15)	I2^iv—Pb1—I2^v	179.3 (3)
I1_2^i—Pb1—I2^ii	89.90 (14)	Pb1—I1_1—Pb1^viii	180.0 (5)
I1_2^i—Pb1—I2^iii	89.90 (14)	Pb1^ix—I1_2—Pb1^viii	180.0 (5)
I1_2^i—Pb1—I2^iv	89.63 (15)	Pb1^x—I2—Pb1^xi	168.13 (12)
I1_2^i—Pb1—I2^v	89.63 (15)	Pb1^x—I2—O1^vi	93.64 (9)
I2^ii—Pb1—I2^iii	179.8 (3)	Pb1^xi—I2—O1^vi	97.71 (13)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1n1···I1_2^xii	1.00	2.88	3.76 (5)	146.48
N2—H1n2···I1_2^xii	1.00	2.84	3.79 (4)	158.44
N1—H2n1···I1_1^x	1.00	3.09	3.93 (5)	142.64
N2—H2n2···I1_1	1.00	3.03	4.02 (4)	167.76
N1—H3n1···I2^xiii	1.00	3.06	3.95 (4)	149.20
N1—H3n1···O1^xiv	1.00	2.85	3.67 (8)	139.55
N2—H3n2···O1^vii	1.00	1.16	2.12 (7)	160.58
C1—H3c1···I2^xv	1.00	2.63	3.60 (5)	163.83
C2—H3c2···O1^xiv	1.00	2.69	3.62 (8)	154.90

Symmetry codes: (vii) −x−1/2, y−1/2, −z+3/2; (x) x, y+1, z; (xii) −y−1/2, x+1/2, z+1/2; (xiii) y−1, x, −z+1; (xiv) y−1, x+1, −z+1; (xv) x−1/2, −y+3/2, −z+3/2.