[1-(1H-Imidazo[4,5-f][1,10]phenanthro­lin-2-yl)naphthalen-2-ol-κ2N7,N8]diiodidomercury(II)

Li, T.-L.

doi:10.1107/S1600536811037160

metal-organic compounds

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ISSN: 2056-9890

Volume 67| Part 10| October 2011| Page m1396

https://doi.org/10.1107/S1600536811037160

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[1-(1H-Imidazo[4,5-f][1,10]phenanthrolin-2-yl)naphthalen-2-ol-κ²N⁷,N⁸]diiodidomercury(II)

Tian-Le Li ^a ^*

^aPhysics Department, School of Science, Guangdong University of Petrochemical Technology, Maoming 525000, People's Republic of China
^*Correspondence e-mail: litianle2009@yahoo.com.cn

(Received 12 September 2011; accepted 13 September 2011; online 17 September 2011)

In the title compound, [HgI₂(C₂₃H₁₄N₄O)], the Hg^II atom is four-coordinated by two N atoms from one 1-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)naphthalen-2-ol ligand and by two I atoms in a distorted tetrahedral environment. An intramolecular O—H⋯N hydrogen bond stabilizes the molecular conformation and an intermolecular N—H⋯I interaction stabilizes the crystal packing.

Related literature

For information about the organic ligand 1-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)naphthalen-2-ol), see: Wang et al. (2010 ).

Experimental

Crystal data

[HgI₂(C₂₃H₁₄N₄O)]
M_r = 816.77
Monoclinic, P 2₁ /c
a = 14.4271 (10) Å
b = 7.3026 (5) Å
c = 21.1337 (15) Å
β = 94.472 (1)°
V = 2219.8 (3) Å³
Z = 4
Mo Kα radiation
μ = 9.74 mm⁻¹
T = 293 K
0.17 × 0.14 × 0.12 mm

Data collection

Bruker SMART APEX diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.41, T_max = 0.64
11586 measured reflections
4351 independent reflections
3217 reflections with I > 2σ(I)
R_int = 0.031

Refinement

R[F² > 2σ(F²)] = 0.029
wR(F²) = 0.057
S = 1.01
4351 reflections
284 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.67 e Å⁻³
Δρ_min = −0.84 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H3A⋯I1ⁱ	0.86	3.05	3.896 (4)	167
O1—H1A⋯N4	0.91 (8)	1.77 (8)	2.623 (6)	155 (7)
Symmetry code: (i) -x+1, -y+1, -z.

Data collection: SMART (Bruker, 1997 ); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536811037160/bt5643sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811037160/bt5643Isup2.hkl

checkCIF report

Comment top

The ligand 1-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)naphthalen-2-ol) is a N-donor ligand and has excellent coordinating ability (Wang et al., 2010). In this work, we selected it as an N-donor chelating ligand, generating a new Hg^II complex.

In the compound, the central Hg^II atom is four-coordinated by two N atoms from one organic ligand, and two I atoms in a distorted tetrahedral sphere. N-H···I and O-H···N H-bonding interactions stabilize the crystal structure and the molecular conformation.

Related literature top

For information about the organic ligand 1-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)naphthalen-2-ol), see: Wang et al. (2010).

Experimental top

A mixture of HgI₂ (0.5 mmol) and 1-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)naphthalen-2-ol) (0.5 mmol) in 8 mL distilled water was heated at 462 K in a Teflon-lined stainless steel autoclave for seven days. The reaction system was then slowly cooled to room temperature. Pale yellow crystals of the title compound suitable for single crystal X-ray diffraction analysis were collected from the final reaction system by filtration, washed several times with distilled water and dried in air at ambient temperature. Yield: 15% based on Hg(II).

Structure description top

For information about the organic ligand 1-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)naphthalen-2-ol), see: Wang et al. (2010).

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. Perspective view of the title compound, showing the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.

[1-(1H-Imidazo[4,5-f][1,10]phenanthrolin-2-yl)naphthalen-2-ol- κ²N⁷,N⁸]diiodidomercury(II) top

Crystal data top

[HgI₂(C₂₃H₁₄N₄O)]	F(000) = 1496
M_r = 816.77	D_x = 2.444 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 4351 reflections
a = 14.4271 (10) Å	θ = 1.9–26.0°
b = 7.3026 (5) Å	µ = 9.74 mm⁻¹
c = 21.1337 (15) Å	T = 293 K
β = 94.472 (1)°	Block, pale yellow
V = 2219.8 (3) Å³	0.17 × 0.14 × 0.12 mm
Z = 4

Data collection top

Bruker SMART APEX diffractometer	4351 independent reflections
Radiation source: fine-focus sealed tube	3217 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.031
φ and ω scans	θ_max = 26.0°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −16→17
T_min = 0.41, T_max = 0.64	k = −7→9
11586 measured reflections	l = −25→26

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.029	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.057	H atoms treated by a mixture of independent and constrained refinement
S = 1.01	w = 1/[σ²(F_o²) + (0.0207P)² + 0.5359P] where P = (F_o² + 2F_c²)/3
4351 reflections	(Δ/σ)_max = 0.002
284 parameters	Δρ_max = 0.67 e Å⁻³
0 restraints	Δρ_min = −0.84 e Å⁻³

Crystal data top

[HgI₂(C₂₃H₁₄N₄O)]	V = 2219.8 (3) Å³
M_r = 816.77	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 14.4271 (10) Å	µ = 9.74 mm⁻¹
b = 7.3026 (5) Å	T = 293 K
c = 21.1337 (15) Å	0.17 × 0.14 × 0.12 mm
β = 94.472 (1)°

Data collection top

Bruker SMART APEX diffractometer	4351 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3217 reflections with I > 2σ(I)
T_min = 0.41, T_max = 0.64	R_int = 0.031
11586 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.029	0 restraints
wR(F²) = 0.057	H atoms treated by a mixture of independent and constrained refinement
S = 1.01	Δρ_max = 0.67 e Å⁻³
4351 reflections	Δρ_min = −0.84 e Å⁻³
284 parameters

Special details top

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.

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 > 2sigma(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
C2	0.8132 (4)	0.3909 (8)	−0.2038 (3)	0.0445 (14)
H2	0.8549	0.3558	−0.2330	0.053*
C7	0.6301 (4)	0.7203 (7)	0.0288 (2)	0.0479 (15)
H7	0.6592	0.7552	0.0677	0.058*
C8	0.5367 (4)	0.7611 (8)	0.0162 (2)	0.0465 (14)
H8	0.5047	0.8245	0.0459	0.056*
C9	0.4920 (4)	0.7077 (7)	−0.0400 (2)	0.0387 (13)
H9	0.4290	0.7309	−0.0488	0.046*
C10	0.5440 (3)	0.6156 (6)	−0.0847 (2)	0.0292 (11)
C11	0.5070 (3)	0.5568 (6)	−0.1458 (2)	0.0291 (11)
C13	0.4226 (3)	0.4818 (6)	−0.2345 (2)	0.0308 (11)
C14	0.3454 (3)	0.4641 (7)	−0.2832 (2)	0.0344 (12)
C15	0.3641 (4)	0.5059 (7)	−0.3451 (2)	0.0434 (13)
C16	0.2540 (4)	0.4097 (8)	−0.2700 (3)	0.0424 (14)
C17	0.2914 (5)	0.5155 (8)	−0.3934 (3)	0.0595 (18)
H17	0.3039	0.5523	−0.4340	0.071*
C18	0.2032 (5)	0.4714 (8)	−0.3811 (3)	0.0593 (18)
H18	0.1557	0.4787	−0.4133	0.071*
C19	0.1830 (4)	0.4155 (8)	−0.3208 (3)	0.0546 (17)
C20	0.0924 (5)	0.3593 (10)	−0.3092 (4)	0.083 (2)
H20	0.0451	0.3663	−0.3416	0.099*
C21	0.0735 (5)	0.2951 (11)	−0.2514 (5)	0.090 (3)
H21	0.0131	0.2589	−0.2448	0.108*
C22	0.1429 (5)	0.2820 (10)	−0.2013 (3)	0.075 (2)
H22	0.1294	0.2351	−0.1621	0.091*
C23	0.2314 (4)	0.3399 (8)	−0.2110 (3)	0.0563 (17)
H23	0.2775	0.3327	−0.1778	0.068*
N3	0.4179 (3)	0.5490 (5)	−0.17388 (18)	0.0316 (10)
H3A	0.3681	0.5804	−0.1567	0.038*
O1	0.4506 (3)	0.5473 (6)	−0.36141 (19)	0.0563 (11)
H1A	0.488 (5)	0.518 (10)	−0.326 (4)	0.12 (3)*
C1	0.8439 (4)	0.4232 (8)	−0.1411 (3)	0.0466 (14)
H1	0.9066	0.4048	−0.1290	0.056*
C3	0.7213 (4)	0.4112 (7)	−0.2222 (2)	0.0395 (13)
H3	0.6990	0.3871	−0.2639	0.047*
C4	0.6609 (3)	0.4691 (6)	−0.1774 (2)	0.0313 (11)
C5	0.6970 (3)	0.5071 (6)	−0.1156 (2)	0.0323 (11)
C6	0.6386 (3)	0.5855 (6)	−0.0694 (2)	0.0298 (11)
C12	0.5631 (3)	0.4922 (6)	−0.1909 (2)	0.0301 (11)
N1	0.6800 (3)	0.6338 (6)	−0.01211 (19)	0.0390 (11)
N2	0.7895 (3)	0.4787 (5)	−0.09743 (19)	0.0375 (10)
N4	0.5108 (3)	0.4486 (5)	−0.24611 (18)	0.0316 (10)
Hg1	0.837535 (16)	0.50252 (3)	0.013119 (11)	0.05187 (8)
I1	0.78377 (3)	0.23045 (5)	0.087966 (19)	0.05635 (12)
I2	0.96077 (3)	0.77042 (5)	0.026201 (19)	0.05224 (12)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C2	0.039 (3)	0.053 (4)	0.043 (3)	0.006 (3)	0.014 (3)	0.005 (3)
C7	0.070 (4)	0.047 (4)	0.026 (3)	−0.011 (3)	0.003 (3)	−0.006 (3)
C8	0.064 (4)	0.047 (4)	0.029 (3)	0.001 (3)	0.010 (3)	−0.004 (3)
C9	0.041 (3)	0.041 (3)	0.035 (3)	0.005 (2)	0.013 (2)	0.003 (3)
C10	0.035 (3)	0.026 (3)	0.027 (3)	−0.002 (2)	0.003 (2)	0.004 (2)
C11	0.029 (3)	0.033 (3)	0.025 (3)	0.000 (2)	0.003 (2)	0.001 (2)
C13	0.042 (3)	0.026 (3)	0.025 (2)	−0.003 (2)	0.005 (2)	0.002 (2)
C14	0.040 (3)	0.037 (3)	0.026 (3)	0.000 (2)	0.002 (2)	−0.003 (2)
C15	0.060 (4)	0.033 (3)	0.035 (3)	0.006 (3)	−0.007 (3)	−0.003 (3)
C16	0.037 (3)	0.044 (3)	0.046 (3)	0.007 (3)	0.000 (3)	−0.015 (3)
C17	0.099 (6)	0.042 (4)	0.034 (3)	0.013 (4)	−0.015 (3)	−0.005 (3)
C18	0.073 (5)	0.049 (4)	0.050 (4)	0.018 (3)	−0.029 (3)	−0.016 (3)
C19	0.046 (4)	0.044 (4)	0.070 (5)	0.015 (3)	−0.020 (3)	−0.021 (3)
C20	0.043 (5)	0.086 (6)	0.115 (7)	0.014 (4)	−0.016 (4)	−0.039 (5)
C21	0.037 (4)	0.095 (6)	0.140 (8)	−0.002 (4)	0.018 (5)	−0.048 (6)
C22	0.060 (5)	0.094 (6)	0.077 (5)	−0.018 (4)	0.033 (4)	−0.033 (4)
C23	0.049 (4)	0.071 (4)	0.051 (4)	−0.009 (3)	0.013 (3)	−0.024 (3)
N3	0.035 (2)	0.034 (2)	0.026 (2)	−0.0019 (18)	0.0057 (18)	−0.0040 (18)
O1	0.071 (3)	0.066 (3)	0.033 (2)	−0.006 (2)	0.012 (2)	0.001 (2)
C1	0.029 (3)	0.058 (4)	0.052 (4)	0.003 (3)	0.004 (3)	0.007 (3)
C3	0.042 (3)	0.042 (3)	0.035 (3)	0.004 (2)	0.005 (3)	−0.001 (3)
C4	0.033 (3)	0.030 (3)	0.031 (3)	0.000 (2)	0.006 (2)	0.002 (2)
C5	0.034 (3)	0.024 (3)	0.038 (3)	−0.002 (2)	0.002 (2)	0.003 (2)
C6	0.039 (3)	0.027 (3)	0.024 (3)	−0.006 (2)	0.002 (2)	0.006 (2)
C12	0.034 (3)	0.028 (3)	0.028 (3)	−0.002 (2)	0.002 (2)	0.001 (2)
N1	0.047 (3)	0.038 (3)	0.031 (2)	−0.006 (2)	−0.004 (2)	0.003 (2)
N2	0.032 (2)	0.040 (3)	0.040 (2)	0.000 (2)	−0.0001 (19)	0.004 (2)
N4	0.033 (2)	0.037 (2)	0.025 (2)	−0.0007 (18)	0.0039 (18)	−0.0021 (18)
Hg1	0.04968 (14)	0.05769 (16)	0.04649 (14)	−0.01629 (12)	−0.00742 (10)	0.00740 (13)
I1	0.0555 (2)	0.0551 (3)	0.0607 (3)	0.00396 (19)	0.0187 (2)	0.0143 (2)
I2	0.0464 (2)	0.0458 (2)	0.0623 (3)	−0.00957 (18)	−0.00981 (18)	0.0071 (2)

Geometric parameters (Å, º) top

C2—C3	1.361 (7)	C18—H18	0.9300
C2—C1	1.385 (7)	C19—C20	1.410 (9)
C2—H2	0.9300	C20—C21	1.357 (11)
C7—N1	1.327 (6)	C20—H20	0.9300
C7—C8	1.385 (8)	C21—C22	1.403 (10)
C7—H7	0.9300	C21—H21	0.9300
C8—C9	1.363 (7)	C22—C23	1.375 (8)
C8—H8	0.9300	C22—H22	0.9300
C9—C10	1.420 (6)	C23—H23	0.9300
C9—H9	0.9300	N3—H3A	0.8600
C10—C6	1.396 (6)	O1—H1A	0.91 (8)
C10—C11	1.425 (6)	C1—N2	1.322 (6)
C11—N3	1.375 (6)	C1—H1	0.9300
C11—C12	1.381 (6)	C3—C4	1.402 (6)
C13—N4	1.337 (6)	C3—H3	0.9300
C13—N3	1.378 (6)	C4—C5	1.396 (7)
C13—C14	1.463 (6)	C4—C12	1.427 (6)
C14—C15	1.391 (7)	C5—N2	1.374 (6)
C14—C16	1.425 (7)	C5—C6	1.456 (6)
C15—O1	1.355 (7)	C6—N1	1.354 (6)
C15—C17	1.407 (8)	C12—N4	1.376 (6)
C16—C23	1.409 (8)	N1—Hg1	2.486 (4)
C16—C19	1.425 (7)	N2—Hg1	2.391 (4)
C17—C18	1.358 (9)	Hg1—I2	2.6435 (4)
C17—H17	0.9300	Hg1—I1	2.6912 (5)
C18—C19	1.389 (9)

C3—C2—C1	119.2 (5)	C20—C21—H21	119.3
C3—C2—H2	120.4	C22—C21—H21	119.3
C1—C2—H2	120.4	C23—C22—C21	118.9 (7)
N1—C7—C8	123.2 (5)	C23—C22—H22	120.6
N1—C7—H7	118.4	C21—C22—H22	120.6
C8—C7—H7	118.4	C22—C23—C16	121.7 (6)
C9—C8—C7	119.4 (5)	C22—C23—H23	119.2
C9—C8—H8	120.3	C16—C23—H23	119.2
C7—C8—H8	120.3	C11—N3—C13	107.6 (4)
C8—C9—C10	118.5 (5)	C11—N3—H3A	126.2
C8—C9—H9	120.8	C13—N3—H3A	126.2
C10—C9—H9	120.8	C15—O1—H1A	103 (5)
C6—C10—C9	118.6 (5)	N2—C1—C2	123.9 (5)
C6—C10—C11	116.9 (4)	N2—C1—H1	118.1
C9—C10—C11	124.5 (4)	C2—C1—H1	118.1
N3—C11—C12	105.5 (4)	C2—C3—C4	118.9 (5)
N3—C11—C10	132.4 (4)	C2—C3—H3	120.5
C12—C11—C10	122.1 (4)	C4—C3—H3	120.5
N4—C13—N3	110.6 (4)	C5—C4—C3	119.0 (4)
N4—C13—C14	122.6 (4)	C5—C4—C12	117.1 (4)
N3—C13—C14	126.5 (4)	C3—C4—C12	123.9 (5)
C15—C14—C16	119.7 (5)	N2—C5—C4	121.1 (4)
C15—C14—C13	116.7 (4)	N2—C5—C6	118.1 (4)
C16—C14—C13	123.6 (4)	C4—C5—C6	120.8 (4)
O1—C15—C14	122.6 (5)	N1—C6—C10	121.4 (5)
O1—C15—C17	117.0 (5)	N1—C6—C5	117.7 (4)
C14—C15—C17	120.3 (6)	C10—C6—C5	120.9 (4)
C23—C16—C19	118.4 (5)	N4—C12—C11	110.6 (4)
C23—C16—C14	123.7 (5)	N4—C12—C4	127.6 (4)
C19—C16—C14	117.8 (5)	C11—C12—C4	121.7 (4)
C18—C17—C15	120.4 (6)	C7—N1—C6	118.8 (5)
C18—C17—H17	119.8	C7—N1—Hg1	125.3 (3)
C15—C17—H17	119.8	C6—N1—Hg1	115.0 (3)
C17—C18—C19	120.8 (6)	C1—N2—C5	117.9 (4)
C17—C18—H18	119.6	C1—N2—Hg1	124.2 (3)
C19—C18—H18	119.6	C5—N2—Hg1	117.6 (3)
C18—C19—C20	120.6 (6)	C13—N4—C12	105.6 (4)
C18—C19—C16	120.6 (6)	N2—Hg1—N1	68.14 (14)
C20—C19—C16	118.8 (7)	N2—Hg1—I2	107.31 (9)
C21—C20—C19	120.8 (7)	N1—Hg1—I2	109.47 (10)
C21—C20—H20	119.6	N2—Hg1—I1	116.46 (9)
C19—C20—H20	119.6	N1—Hg1—I1	96.33 (9)
C20—C21—C22	121.4 (7)	I2—Hg1—I1	135.010 (15)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3A···I1ⁱ	0.86	3.05	3.896 (4)	167
O1—H1A···N4	0.91 (8)	1.77 (8)	2.623 (6)	155 (7)

Symmetry code: (i) −x+1, −y+1, −z.

Experimental details

Crystal data
Chemical formula	[HgI₂(C₂₃H₁₄N₄O)]
M_r	816.77
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	14.4271 (10), 7.3026 (5), 21.1337 (15)
β (°)	94.472 (1)
V (Å³)	2219.8 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	9.74
Crystal size (mm)	0.17 × 0.14 × 0.12

Data collection
Diffractometer	Bruker SMART APEX
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.41, 0.64
No. of measured, independent and observed [I > 2σ(I)] reflections	11586, 4351, 3217
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.029, 0.057, 1.01
No. of reflections	4351
No. of parameters	284
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.67, −0.84

Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3A···I1ⁱ	0.86	3.05	3.896 (4)	167.2
O1—H1A···N4	0.91 (8)	1.77 (8)	2.623 (6)	155 (7)

Symmetry code: (i) −x+1, −y+1, −z.

Acknowledgements

The author thanks Guangdong University of Petrochemical Technology for supporting this work.

References

Bruker (1997). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Wang, X. Y., Ma, X. Y., Liu, Y., Xu, Z. L. & Kong, Z. G. (2010). Chin. J. Inorg. Chem. 26, 1482–1484. CAS Google Scholar

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