cis-Dichloridobis(dimethoxy­phenyl­phosphine)palladium(II)

Slawin, A.M.Z.; Waddell, P.G.; Woollins, J.D.

doi:10.1107/S1600536810006471

metal-organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 66| Part 3| March 2010| Page m321

doi:10.1107/S1600536810006471

Open

access

cis-Dichloridobis(dimethoxyphenylphosphine)palladium(II)

Alexandra M. Z. Slawin,^a ^* Paul G. Waddell ^a and J. Derek Woollins ^a

^aDepartment of Chemistry, University of St Andrews, St Andrews KY16 9ST, Scotland
^*Correspondence e-mail: amzs@st-and.ac.uk

(Received 16 February 2010; accepted 19 February 2010; online 24 February 2010)

The title compound, [PdCl₂(C₈H₁₁O₂P)₂], has a comparable structure to those of related palladium dichloride complexes containing trimethyl phosphinite and methyl diphenyl phosphinite. The Pd atom is located on a crystallographic twofold rotation axis: thus, there is just one half-molecule in the asymmetric unit. The structure is isomorphous with the platinum analogue cis-[PtCl₂{P(OMe)₂Ph}₂].

Related literature

For related structures, see: Slawin et al. (2009 , 2007 ); Powell & Jacobson (1980 ). For preparation of the title compound, see: Jenkins & Shaw (1966 ).

Experimental

Crystal data

[PdCl₂(C₈H₁₁O₂P)₂]
M_r = 517.60
Monoclinic, C 2/c
a = 10.876 (7) Å
b = 9.174 (5) Å
c = 20.722 (13) Å
β = 102.196 (7)°
V = 2021 (2) Å³
Z = 4
Mo Kα radiation
μ = 1.36 mm⁻¹
T = 125 K
0.16 × 0.15 × 0.09 mm

Data collection

Rigaku Mercury CCD diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ) T_min = 0.812, T_max = 0.888
8406 measured reflections
1775 independent reflections
1653 reflections with F² > 2σ(F²)
R_int = 0.032

Refinement

R[F² > 2σ(F²)] = 0.023
wR(F²) = 0.050
S = 1.09
1775 reflections
117 parameters
All H-atom parameters refined
Δρ_max = 1.15 e Å⁻³
Δρ_min = −0.32 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Pd1—Cl1	2.3515 (16)
Pd1—P1	2.2300 (16)

Cl1—Pd1—Cl1ⁱ	91.49 (2)
Cl1—Pd1—P1	174.86 (2)
Cl1—Pd1—P1ⁱ	83.85 (2)
P1—Pd1—P1ⁱ	100.88 (2)
Symmetry code: (i) $[-x, y, -z+{\script{3\over 2}}]$ .

Data collection: SCXmini (Rigaku/MSC, 2006 ); cell refinement: PROCESS-AUTO (Rigaku, 1998 ); data reduction: PROCESS-AUTO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CrystalStructure (Rigaku/MSC, 2006); software used to prepare material for publication: CrystalStructure.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810006471/bt5195sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810006471/bt5195Isup2.hkl

checkCIF report

Related literature top

For related structures, see: Slawin et al. (2009, 2007); Powell et al. (1980). For preparation of the title compound, see: Jenkins & Shaw (1966).

Experimental top

Based on the method of Jenkins & Shaw (1966). To (0.3 g (0.93 mmol) of potassium tetrachloropalladate was dissolved in 10 ml e thanol and 0.147 ml (1.86 mmol) of P(OMe)₂Ph was added. The solution was stirred at room temperature for 30 min s before being filtered and then precipitated by slow addition of hexane to give a white crystalline solid. Crystals were grown for X-ray crystallography via slow diffusion of hexane into a solution of the product in dichloromethane [cis-PdCl₂(P(OMe)₂Ph)₂] (0.40 mmol, ca. 68 %). ³¹P-{¹H} NMR: δ 125.8 ppm.

Computing details top

Data collection: SCXmini (Rigaku/MSC, 2006); cell refinement: PROCESS-AUTO (Rigaku, 1998); data reduction: PROCESS-AUTO (Rigaku, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CrystalStructure (Rigaku/MSC, 2006); software used to prepare material for publication: CrystalStructure (Rigaku/MSC, 2006).

Figures top

Fig. 1. The structure of the title compound with displacement ellipsoids drawn at the 50% probability level, hydrogen atoms omitted for clarity. Symmetry operator for generating equivalent atoms (A): -x, y, 1.5-z.

cis-Dichloridobis(dimethoxyphenylphosphine)palladium(II) top

Crystal data top

[PdCl₂(C₈H₁₁O₂P)₂]	F(000) = 1040.00
M_r = 517.60	D_x = 1.701 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71075 Å
Hall symbol: -C 2yc	Cell parameters from 2591 reflections
a = 10.876 (7) Å	θ = 2.9–25.4°
b = 9.174 (5) Å	µ = 1.36 mm⁻¹
c = 20.722 (13) Å	T = 125 K
β = 102.196 (7)°	Prism, colorless
V = 2021 (2) Å³	0.16 × 0.15 × 0.09 mm
Z = 4

Data collection top

Rigaku Mercury CCD diffractometer	1653 reflections with F² > 2σ(F²)
Detector resolution: 0.83 pixels mm^-1	R_int = 0.032
ω scans	θ_max = 25.0°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −13→13
T_min = 0.812, T_max = 0.888	k = −11→11
8406 measured reflections	l = −24→24
1775 independent reflections

Refinement top

Refinement on F²	All H-atom parameters refined
R[F² > 2σ(F²)] = 0.023	w = 1/[σ²(F_o²) + (0.0162P)² + 4.843P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.050	(Δ/σ)_max = 0.001
S = 1.09	Δρ_max = 1.15 e Å⁻³
1775 reflections	Δρ_min = −0.32 e Å⁻³
117 parameters

Crystal data top

[PdCl₂(C₈H₁₁O₂P)₂]	V = 2021 (2) Å³
M_r = 517.60	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 10.876 (7) Å	µ = 1.36 mm⁻¹
b = 9.174 (5) Å	T = 125 K
c = 20.722 (13) Å	0.16 × 0.15 × 0.09 mm
β = 102.196 (7)°

Data collection top

Rigaku Mercury CCD diffractometer	1775 independent reflections
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	1653 reflections with F² > 2σ(F²)
T_min = 0.812, T_max = 0.888	R_int = 0.032
8406 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.023	117 parameters
wR(F²) = 0.050	All H-atom parameters refined
S = 1.09	Δρ_max = 1.15 e Å⁻³
1775 reflections	Δρ_min = −0.32 e Å⁻³

Special details top

Geometry. ENTER SPECIAL DETAILS OF THE MOLECULAR GEOMETRY

Refinement. Refinement was performed using all reflections. The weighted R-factor (wR) and goodness of fit (S) are based on F². R-factor (gt) are based on F. The threshold expression of F² > 2.0 σ(F²) is used only for calculating R-factor (gt).

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

	x	y	z	U_iso*/U_eq
Pd1	0.0000	0.09671 (3)	0.7500	0.01397 (8)
Cl1	−0.09211 (6)	−0.08216 (6)	0.67365 (3)	0.02090 (14)
P1	0.10038 (6)	0.25152 (7)	0.82618 (3)	0.01521 (14)
O1	0.24303 (15)	0.21038 (18)	0.85487 (8)	0.0189 (3)
O2	0.10272 (16)	0.41579 (17)	0.80284 (8)	0.0199 (3)
C1	0.0398 (2)	0.2542 (2)	0.90033 (12)	0.0172 (5)
C2	0.0988 (2)	0.1823 (2)	0.95758 (12)	0.0220 (5)
C3	0.0459 (2)	0.1856 (3)	1.01266 (13)	0.0285 (6)
C4	−0.0648 (2)	0.2601 (3)	1.01080 (13)	0.0302 (6)
C5	−0.1248 (2)	0.3298 (3)	0.95385 (14)	0.0328 (6)
C6	−0.0733 (2)	0.3264 (2)	0.89844 (13)	0.0259 (5)
C7	0.3242 (2)	0.1770 (3)	0.80984 (14)	0.0278 (6)
C8	0.1786 (2)	0.5209 (2)	0.84682 (13)	0.0274 (6)
H1	0.2993	0.0858	0.7883	0.033*
H2	0.1736	0.1321	0.9588	0.026*
H3	0.0851	0.1376	1.0510	0.034*
H4	−0.0994	0.2634	1.0482	0.036*
H5	−0.1999	0.3791	0.9528	0.039*
H6	−0.1143	0.3724	0.8599	0.031*
H7	0.4097	0.1704	0.8340	0.033*
H8	0.3175	0.2528	0.7773	0.033*
H9	0.1697	0.5038	0.8913	0.033*
H10	0.1508	0.6179	0.8337	0.033*
H11	0.2654	0.5103	0.8444	0.033*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Pd1	0.01670 (15)	0.01215 (14)	0.01241 (14)	0.0000	0.00162 (10)	0.0000
Cl1	0.0256 (3)	0.0154 (3)	0.0190 (3)	−0.0012 (2)	−0.0014 (2)	−0.0041 (2)
P1	0.0170 (3)	0.0143 (3)	0.0137 (3)	−0.0012 (2)	0.0020 (2)	−0.0000 (2)
O1	0.0154 (8)	0.0217 (8)	0.0194 (8)	−0.0021 (7)	0.0029 (6)	−0.0027 (7)
O2	0.0266 (9)	0.0151 (8)	0.0163 (8)	−0.0040 (6)	0.0002 (7)	0.0006 (6)
C1	0.0198 (12)	0.0159 (12)	0.0159 (11)	−0.0031 (9)	0.0037 (9)	−0.0022 (9)
C2	0.0212 (13)	0.0248 (14)	0.0188 (12)	0.0032 (10)	0.0017 (10)	−0.0012 (10)
C3	0.0336 (15)	0.0356 (16)	0.0153 (13)	−0.0020 (12)	0.0025 (11)	0.0020 (11)
C4	0.0363 (16)	0.0370 (16)	0.0203 (14)	−0.0054 (12)	0.0125 (12)	−0.0051 (12)
C5	0.0279 (15)	0.0383 (17)	0.0352 (16)	0.0073 (12)	0.0132 (12)	0.0003 (13)
C6	0.0265 (14)	0.0271 (14)	0.0245 (14)	0.0048 (11)	0.0062 (11)	0.0048 (11)
C7	0.0239 (14)	0.0317 (15)	0.0308 (15)	−0.0024 (11)	0.0127 (11)	−0.0017 (12)
C8	0.0387 (16)	0.0172 (13)	0.0249 (14)	−0.0079 (11)	0.0034 (12)	−0.0043 (11)

Geometric parameters (Å, º) top

Pd1—Cl1	2.3515 (16)	C4—C5	1.379 (3)
Pd1—Cl1ⁱ	2.3515 (16)	C5—C6	1.380 (4)
Pd1—P1	2.2300 (16)	C2—H2	0.930
Pd1—P1ⁱ	2.2300 (16)	C3—H3	0.930
P1—O1	1.5853 (16)	C4—H4	0.930
P1—O2	1.5846 (17)	C5—H5	0.930
P1—C1	1.795 (2)	C6—H6	0.930
O1—C7	1.446 (3)	C7—H1	0.960
O2—C8	1.458 (2)	C7—H7	0.960
C1—C2	1.390 (3)	C7—H8	0.960
C1—C6	1.391 (3)	C8—H9	0.960
C2—C3	1.383 (4)	C8—H10	0.960
C3—C4	1.378 (4)	C8—H11	0.960

O1···C3ⁱⁱ	3.324 (2)	H3···H9ⁱⁱ	2.979
O2···C7ⁱⁱⁱ	3.551 (3)	H3···H11ⁱⁱ	2.774
C3···O1ⁱⁱ	3.324 (2)	H4···Cl1^xiv	3.073
C3···C3^iv	3.557 (3)	H4···C5^xii	3.112
C7···O2^v	3.551 (3)	H4···C8^xiii	3.191
C7···C8^v	3.542 (3)	H4···H4^xii	3.467
C8···C7ⁱⁱⁱ	3.542 (3)	H4···H5^xii	2.542
Cl1···H3^vi	3.536	H4···H7ⁱⁱ	2.908
Cl1···H4^vi	3.073	H4···H9^xiii	2.669
Cl1···H5^vii	3.099	H4···H10^xiii	2.840
Cl1···H6^vii	3.149	H5···Cl1^xv	3.099
Cl1···H7^v	3.041	H5···C2^xi	3.554
Cl1···H8^viii	2.961	H5···C4^xii	3.093
Cl1···H8^v	3.311	H5···C5^xii	3.552
Cl1···H10^ix	2.822	H5···H2^xi	2.715
O1···H3ⁱⁱ	2.775	H5···H4^xii	2.542
O1···H6^x	3.459	H5···H5^xii	3.396
O2···H1ⁱⁱⁱ	2.826	H5···H9^xiii	3.354
O2···H7^xi	3.294	H5···H10^viii	3.575
C2···H2ⁱⁱ	3.196	H6···Cl1^xv	3.149
C2···H3^iv	3.535	H6···O1^xi	3.459
C2···H5^x	3.554	H6···C7^xi	3.007
C3···H2ⁱⁱ	3.419	H6···H1^xi	2.515
C3···H3^iv	3.431	H6···H7^xi	2.809
C3···H7ⁱⁱ	3.381	H6···H10^viii	3.418
C4···H5^xii	3.093	H6···H11^viii	3.560
C4···H7ⁱⁱ	3.363	H7···Cl1ⁱⁱⁱ	3.041
C4···H9^xiii	3.329	H7···O2^x	3.294
C5···H2^xi	3.551	H7···C3ⁱⁱ	3.381
C5···H4^xii	3.112	H7···C4ⁱⁱ	3.363
C5···H5^xii	3.552	H7···C6^x	3.417
C6···H1^xi	3.384	H7···C8^x	3.190
C6···H7^xi	3.417	H7···H3ⁱⁱ	2.955
C6···H10^viii	3.572	H7···H4ⁱⁱ	2.908
C6···H11^viii	3.451	H7···H6^x	2.809
C7···H3ⁱⁱ	3.313	H7···H9^x	3.213
C7···H6^x	3.007	H7···H10^x	2.668
C7···H10^x	3.523	H7···H10^v	3.431
C7···H10^v	3.092	H8···Cl1^xvi	2.961
C7···H11^v	3.491	H8···Cl1ⁱⁱⁱ	3.311
C8···H1ⁱⁱⁱ	2.922	H8···C8^v	3.345
C8···H3ⁱⁱ	3.301	H8···H1ⁱⁱⁱ	3.474
C8···H4^xiii	3.191	H8···H10^v	2.698
C8···H7^xi	3.190	H8···H11^v	3.341
C8···H8ⁱⁱⁱ	3.345	H9···C4^xiii	3.329
H1···O2^v	2.826	H9···H2ⁱⁱ	3.445
H1···C6^x	3.384	H9···H3ⁱⁱ	2.979
H1···C8^v	2.922	H9···H4^xiii	2.669
H1···H6^x	2.515	H9···H5^xiii	3.354
H1···H8^v	3.474	H9···H7^xi	3.213
H1···H10^v	2.712	H10···Cl1^xvii	2.822
H1···H11^v	2.779	H10···C6^xvi	3.572
H2···C2ⁱⁱ	3.196	H10···C7^xi	3.523
H2···C3ⁱⁱ	3.419	H10···C7ⁱⁱⁱ	3.092
H2···C5^x	3.551	H10···H1ⁱⁱⁱ	2.712
H2···H2ⁱⁱ	3.026	H10···H4^xiii	2.840
H2···H3ⁱⁱ	3.409	H10···H5^xvi	3.575
H2···H5^x	2.715	H10···H6^xvi	3.418
H2···H9ⁱⁱ	3.445	H10···H7^xi	2.668
H3···Cl1^xiv	3.536	H10···H7ⁱⁱⁱ	3.431
H3···O1ⁱⁱ	2.775	H10···H8ⁱⁱⁱ	2.698
H3···C2^iv	3.535	H11···C6^xvi	3.451
H3···C3^iv	3.431	H11···C7ⁱⁱⁱ	3.491
H3···C7ⁱⁱ	3.313	H11···H1ⁱⁱⁱ	2.779
H3···C8ⁱⁱ	3.301	H11···H3ⁱⁱ	2.774
H3···H2ⁱⁱ	3.409	H11···H6^xvi	3.560
H3···H3^iv	3.552	H11···H8ⁱⁱⁱ	3.341
H3···H7ⁱⁱ	2.955

Cl1—Pd1—Cl1ⁱ	91.49 (2)	C1—C2—H2	120.1
Cl1—Pd1—P1	174.86 (2)	C3—C2—H2	120.1
Cl1—Pd1—P1ⁱ	83.85 (2)	C2—C3—H3	120.0
Cl1ⁱ—Pd1—P1	83.85 (2)	C4—C3—H3	120.0
Cl1ⁱ—Pd1—P1ⁱ	174.86 (2)	C3—C4—H4	119.8
P1—Pd1—P1ⁱ	100.88 (2)	C5—C4—H4	119.8
Pd1—P1—O1	114.07 (6)	C4—C5—H5	120.0
Pd1—P1—O2	115.26 (6)	C6—C5—H5	120.0
Pd1—P1—C1	113.66 (7)	C1—C6—H6	120.0
O1—P1—O2	105.27 (9)	C5—C6—H6	120.0
O1—P1—C1	100.91 (10)	O1—C7—H1	109.5
O2—P1—C1	106.30 (10)	O1—C7—H7	109.5
P1—O1—C7	119.39 (14)	O1—C7—H8	109.5
P1—O2—C8	118.82 (14)	H1—C7—H7	109.5
P1—C1—C2	122.50 (19)	H1—C7—H8	109.5
P1—C1—C6	117.70 (18)	H7—C7—H8	109.5
C2—C1—C6	119.7 (2)	O2—C8—H9	109.5
C1—C2—C3	119.8 (2)	O2—C8—H10	109.5
C2—C3—C4	120.1 (2)	O2—C8—H11	109.5
C3—C4—C5	120.4 (2)	H9—C8—H10	109.5
C4—C5—C6	120.0 (2)	H9—C8—H11	109.5
C1—C6—C5	119.9 (2)	H10—C8—H11	109.5

Cl1—Pd1—P1ⁱ—O1ⁱ	47.02 (7)	O1—P1—O2—C8	−46.3 (2)
Cl1—Pd1—P1ⁱ—O2ⁱ	169.01 (8)	O2—P1—O1—C7	−77.89 (18)
Cl1—Pd1—P1ⁱ—C1ⁱ	−67.93 (8)	O1—P1—C1—C2	−21.0 (2)
Cl1ⁱ—Pd1—P1—O1	47.02 (7)	O1—P1—C1—C6	161.81 (18)
Cl1ⁱ—Pd1—P1—O2	169.01 (8)	C1—P1—O1—C7	171.69 (17)
Cl1ⁱ—Pd1—P1—C1	−67.93 (8)	O2—P1—C1—C2	−130.59 (19)
P1—Pd1—P1ⁱ—O1ⁱ	−135.01 (7)	O2—P1—C1—C6	52.2 (2)
P1—Pd1—P1ⁱ—O2ⁱ	−13.03 (8)	C1—P1—O2—C8	60.2 (2)
P1—Pd1—P1ⁱ—C1ⁱ	110.03 (8)	P1—C1—C2—C3	−178.50 (19)
P1ⁱ—Pd1—P1—O1	−135.01 (7)	P1—C1—C6—C5	179.1 (2)
P1ⁱ—Pd1—P1—O2	−13.03 (8)	C2—C1—C6—C5	1.8 (3)
P1ⁱ—Pd1—P1—C1	110.03 (8)	C6—C1—C2—C3	−1.3 (3)
Pd1—P1—O1—C7	49.44 (18)	C1—C2—C3—C4	−0.1 (3)
Pd1—P1—O2—C8	−172.89 (16)	C2—C3—C4—C5	1.0 (4)
Pd1—P1—C1—C2	101.57 (19)	C3—C4—C5—C6	−0.6 (4)
Pd1—P1—C1—C6	−75.6 (2)	C4—C5—C6—C1	−0.8 (4)

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

Experimental details

Crystal data
Chemical formula	[PdCl₂(C₈H₁₁O₂P)₂]
M_r	517.60
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	125
a, b, c (Å)	10.876 (7), 9.174 (5), 20.722 (13)
β (°)	102.196 (7)
V (Å³)	2021 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	1.36
Crystal size (mm)	0.16 × 0.15 × 0.09

Data collection
Diffractometer	Rigaku Mercury CCD diffractometer
Absorption correction	Multi-scan (ABSCOR; Higashi, 1995)
T_min, T_max	0.812, 0.888
No. of measured, independent and observed [F² > 2σ(F²)] reflections	8406, 1775, 1653
R_int	0.032
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.023, 0.050, 1.09
No. of reflections	1775
No. of parameters	117
No. of restraints	?
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	1.15, −0.32

Computer programs: SCXmini (Rigaku/MSC, 2006), PROCESS-AUTO (Rigaku, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), CrystalStructure (Rigaku/MSC, 2006).

Selected geometric parameters (Å, º) top

Pd1—Cl1	2.3515 (16)	Pd1—P1	2.2300 (16)

Cl1—Pd1—Cl1ⁱ	91.49 (2)	Cl1—Pd1—P1ⁱ	83.85 (2)
Cl1—Pd1—P1	174.86 (2)	P1—Pd1—P1ⁱ	100.88 (2)

Symmetry code: (i) −x, y, −z+3/2.

References

Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan. Google Scholar
Jenkins, J. M. & Shaw, B. L. (1966). J. Chem. Soc. A, pp. 770–774. CrossRef Google Scholar
Powell, D. R. & Jacobson, R. A. (1980). Cryst. Struct. Commun. 9, 1023–1027. CAS Google Scholar
Rigaku (1998). PROCESS-AUTO. Rigaku Corporation, Tokyo, Japan. Google Scholar
Rigaku/MSC (2006). CrystalStructure and SCXmini Benchtop Crystallography System Software. Rigaku/MSC, The Woodlands, Texas, USA. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Slawin, A. M. Z., Waddell, P. G. & Woollins, J. D. (2007). Acta Cryst. E63, m2017. Web of Science CSD CrossRef IUCr Journals Google Scholar
Slawin, A. M. Z., Waddell, P. G. & Woollins, J. D. (2009). Acta Cryst. E65, m1391. Web of Science CrossRef IUCr Journals Google Scholar