Aqua­chloridobis[5-(2-pyrid­yl)-1H-tetra­zolato-κN1]iron(III)

Wang, B.

doi:10.1107/S160053680902443X

metal-organic compounds

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Volume 65| Part 8| August 2009| Page m861

doi:10.1107/S160053680902443X

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Aquachloridobis[5-(2-pyridyl)-1H-tetrazolato-κN¹]iron(III)

Bo Wang ^a ^*

^aOrdered Matter Science Research Center, College of Chemistry and Chemical Engineering, Southeast University, Nanjing 210096, People's Republic of China
^*Correspondence e-mail: fudavid88@yahoo.com.cn

(Received 20 June 2009; accepted 24 June 2009; online 1 July 2009)

The title compound, [Fe(C₆H₄N₅)₂Cl(H₂O)], was synthesized by hydrothermal reaction of FeCl₃ with 2-(1H-tetrazol-5-yl)pyridine. The iron(III) metal centre exhibits a distorted octahedral coordination geometry provided by four N atoms from two bidentate organic ligands, one water O atom and one chloride anion. The pyridine and tetrazole rings are nearly coplanar [dihedral angles = 4.32 (15) and 5.04 (14)°]. In the crystal structure, intermolecular O—H⋯N hydrogen bonds link the complex molecules into a two-dimensional network parallel to (100).

Related literature

For physical properties such as permittivity, fluorescence, magnetism and optical properties of metal-organic coordination compounds, see: Fu et al. (2007 ); Huang et al. (1999 ); Liu et al. (1999 ); Xie et al. (2003 ); Zhang et al. (2000 , 2001 ). For the structure of a related tetrazole compound, see: Fu et al. (2008 ).

Experimental

Crystal data

[Fe(C₆H₄N₅)₂Cl(H₂O)]
M_r = 401.60
Monoclinic, P 2₁ /c
a = 17.072 (3) Å
b = 7.1905 (14) Å
c = 14.292 (3) Å
β = 113.85 (3)°
V = 1604.6 (7) Å³
Z = 4
Mo Kα radiation
μ = 1.13 mm⁻¹
T = 298 K
0.15 × 0.10 × 0.10 mm

Data collection

Rigaku Mercury2 diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005 ) T_min = 0.867, T_max = 0.894
15693 measured reflections
3678 independent reflections
3226 reflections with I > 2σ(I)
R_int = 0.040

Refinement

R[F² > 2σ(F²)] = 0.034
wR(F²) = 0.080
S = 1.13
3678 reflections
226 parameters
H-atom parameters constrained
Δρ_max = 0.33 e Å⁻³
Δρ_min = −0.37 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H1WA⋯N4ⁱ	0.98	1.67	2.652 (2)	178
O1W—H1WB⋯N9ⁱⁱ	0.82	1.80	2.626 (2)	176
Symmetry codes: (i) x, y-1, z; (ii) $[x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL/PC (Sheldrick, 2008); software used to prepare material for publication: SHELXTL/PC.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053680902443X/rz2339sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053680902443X/rz2339Isup2.hkl

checkCIF report

Comment top

The construction of metal-organic coordination compounds has attracted much attention owing to their potential propertiess, such as permittivity, fluorescence, magnetism and optical properties. (Fu et al., 2007; Huang et al., 1999; Liu et al., 1999; Xie et al., 2003; Zhang et al.,2001; Zhang et al.,2000). Tetrazole compounds are a class of excellent ligands for the construction of novel metal-organic frameworks, because of their various coordination modes. (Fu et al., 2008). Herein the crystal structure of the title compound is reported.

In the title compound (Fig. 1), the distorted octahedral coordination geometry around the iron(III) metal centre is provided by four N atoms from two bidentate 2-(1H-tetrazol-5-yl)pyridine ligands, one water O atom and one chloride ion. The pyridine and tetrazole rings are nearly coplanar and only twisted by a dihedral angle of 4.32 (15) and 5.04 (14)°. The geometric parameters of the tetrazole rings are comparable to those observed in a related molecule (Fu et al., 2008). The water molecules are involved in intermolecular O—H···N hydrogen bonds (Table 1) generating a two-dimensional network (Fig. 2).

Related literature top

For physical properties such as permittivity, fluorescence, magnetism and optical properties of metal-organic coordination compounds, see: Fu et al. (2007); Huang et al. (1999); Liu et al. (1999); Xie et al. (2003); Zhang et al. (2001); Zhang et al. (2000). For the structure of a related tetrazole compound, see: Fu et al. (2008).

Experimental top

A mixture of 2-(1H-tetrazol-5-yl)pyridine (0.2 mmol), FeCl₃ (0.1 mmol), distilled water (1 ml) and a few drops of ethanol sealed in a glass tube was heated at 85 °C. Colourless block crystals suitable for X-ray analysis were obtained after 10 days.

Computing details top

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL/PC (Sheldrick, 2008); software used to prepare material for publication: SHELXTL/PC (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular view of the title compound with the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 2. The crystal packing of the title compound viewed along the a axis, showing the two dimensionnal hydrogen bondings network (dashed line). Hydrogen atoms not involved in hydrogen bonding have been omitted for clarity.

Aquachloridobis[5-(2-pyridyl)-1H-tetrazolato-κN¹]iron(III) top

Crystal data top

[Fe(C₆H₄N₅)₂Cl(H₂O)]	F(000) = 812
M_r = 401.60	D_x = 1.662 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3226 reflections
a = 17.072 (3) Å	θ = 3.1–27.5°
b = 7.1905 (14) Å	µ = 1.13 mm⁻¹
c = 14.292 (3) Å	T = 298 K
β = 113.85 (3)°	Block, colourless
V = 1604.6 (7) Å³	0.15 × 0.10 × 0.10 mm
Z = 4

Data collection top

Rigaku Mercury2 diffractometer	3678 independent reflections
Radiation source: fine-focus sealed tube	3226 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.040
Detector resolution: 13.6612 pixels mm^-1	θ_max = 27.5°, θ_min = 3.1°
CCD profile fitting scans	h = −22→22
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	k = −9→9
T_min = 0.867, T_max = 0.894	l = −18→18
15693 measured reflections

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)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.080	H-atom parameters constrained
S = 1.13	w = 1/[σ²(F_o²) + (0.0265P)² + 0.8976P] where P = (F_o² + 2F_c²)/3
3678 reflections	(Δ/σ)_max < 0.001
226 parameters	Δρ_max = 0.33 e Å⁻³
0 restraints	Δρ_min = −0.37 e Å⁻³

Crystal data top

[Fe(C₆H₄N₅)₂Cl(H₂O)]	V = 1604.6 (7) Å³
M_r = 401.60	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 17.072 (3) Å	µ = 1.13 mm⁻¹
b = 7.1905 (14) Å	T = 298 K
c = 14.292 (3) Å	0.15 × 0.10 × 0.10 mm
β = 113.85 (3)°

Data collection top

Rigaku Mercury2 diffractometer	3678 independent reflections
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	3226 reflections with I > 2σ(I)
T_min = 0.867, T_max = 0.894	R_int = 0.040
15693 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.034	0 restraints
wR(F²) = 0.080	H-atom parameters constrained
S = 1.13	Δρ_max = 0.33 e Å⁻³
3678 reflections	Δρ_min = −0.37 e Å⁻³
226 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
Fe1	0.244652 (16)	0.52062 (4)	0.23914 (2)	0.02111 (9)
Cl1	0.23959 (4)	0.25457 (8)	0.15658 (4)	0.04015 (15)
O1W	0.24124 (9)	0.4003 (2)	0.36157 (10)	0.0298 (3)
H1WA	0.2559	0.2685	0.3733	0.045*
H1WB	0.2346	0.4617	0.4065	0.045*
N6	0.10878 (10)	0.5759 (2)	0.17945 (13)	0.0252 (4)
N2	0.26988 (10)	0.7731 (2)	0.32361 (13)	0.0233 (3)
N1	0.38334 (10)	0.5417 (2)	0.30588 (13)	0.0277 (4)
N4	0.28121 (13)	1.0424 (2)	0.39005 (15)	0.0369 (5)
C11	0.07709 (12)	0.6877 (3)	0.09684 (15)	0.0250 (4)
N10	0.13543 (12)	0.8769 (3)	−0.00850 (13)	0.0332 (4)
N3	0.22568 (11)	0.9153 (2)	0.33720 (14)	0.0310 (4)
N7	0.22328 (10)	0.6973 (2)	0.11379 (13)	0.0260 (4)
N9	0.21594 (12)	0.8912 (3)	−0.00236 (14)	0.0338 (4)
N8	0.26901 (11)	0.7850 (3)	0.07022 (14)	0.0324 (4)
N5	0.36207 (12)	0.9877 (3)	0.41089 (16)	0.0391 (5)
C5	0.41688 (12)	0.6927 (3)	0.36392 (16)	0.0277 (4)
C6	0.35228 (13)	0.8211 (3)	0.36874 (15)	0.0266 (4)
C12	0.14278 (13)	0.7567 (3)	0.06464 (15)	0.0251 (4)
C10	−0.00933 (13)	0.7286 (3)	0.04887 (17)	0.0345 (5)
H10A	−0.0299	0.8074	−0.0075	0.041*
C4	0.50448 (14)	0.7199 (4)	0.41376 (19)	0.0412 (6)
H4A	0.5264	0.8261	0.4527	0.049*
C8	−0.03227 (14)	0.5360 (4)	0.1706 (2)	0.0419 (6)
H8A	−0.0686	0.4823	0.1970	0.050*
C9	−0.06443 (14)	0.6492 (4)	0.08684 (19)	0.0403 (6)
H9A	−0.1229	0.6729	0.0555	0.048*
C7	0.05448 (14)	0.5021 (3)	0.21553 (18)	0.0370 (5)
H7A	0.0761	0.4255	0.2728	0.044*
C3	0.55837 (15)	0.5858 (4)	0.4041 (2)	0.0501 (7)
H3A	0.6174	0.6006	0.4367	0.060*
C2	0.52448 (15)	0.4307 (4)	0.3465 (2)	0.0524 (7)
H2A	0.5602	0.3387	0.3398	0.063*
C1	0.43723 (15)	0.4126 (4)	0.2986 (2)	0.0436 (6)
H1A	0.4146	0.3068	0.2595	0.052*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Fe1	0.01986 (15)	0.01999 (15)	0.02244 (15)	0.00008 (11)	0.00748 (11)	−0.00171 (11)
Cl1	0.0484 (3)	0.0314 (3)	0.0355 (3)	0.0008 (2)	0.0116 (3)	−0.0137 (2)
O1W	0.0454 (9)	0.0204 (7)	0.0275 (7)	0.0062 (6)	0.0188 (7)	0.0003 (6)
N6	0.0206 (8)	0.0261 (9)	0.0284 (9)	−0.0020 (7)	0.0095 (7)	0.0006 (7)
N2	0.0231 (8)	0.0186 (8)	0.0289 (9)	0.0013 (6)	0.0114 (7)	−0.0012 (7)
N1	0.0222 (8)	0.0314 (9)	0.0288 (9)	0.0024 (7)	0.0095 (7)	−0.0064 (7)
N4	0.0465 (11)	0.0195 (9)	0.0431 (11)	0.0034 (8)	0.0165 (9)	−0.0044 (8)
C11	0.0244 (10)	0.0242 (10)	0.0260 (10)	0.0006 (8)	0.0098 (8)	−0.0027 (8)
N10	0.0421 (11)	0.0280 (10)	0.0302 (9)	0.0018 (8)	0.0155 (8)	0.0042 (8)
N3	0.0358 (10)	0.0210 (9)	0.0396 (10)	0.0064 (7)	0.0186 (8)	0.0011 (8)
N7	0.0255 (8)	0.0282 (9)	0.0279 (9)	−0.0033 (7)	0.0145 (7)	0.0021 (7)
N9	0.0472 (11)	0.0292 (10)	0.0319 (10)	−0.0045 (8)	0.0229 (9)	0.0008 (8)
N8	0.0349 (10)	0.0340 (10)	0.0348 (10)	−0.0060 (8)	0.0210 (8)	−0.0001 (8)
N5	0.0390 (11)	0.0251 (10)	0.0456 (12)	−0.0034 (8)	0.0094 (9)	−0.0092 (8)
C5	0.0237 (10)	0.0301 (11)	0.0272 (10)	−0.0002 (8)	0.0080 (8)	−0.0018 (9)
C6	0.0264 (10)	0.0234 (10)	0.0266 (10)	−0.0021 (8)	0.0071 (8)	−0.0030 (8)
C12	0.0292 (10)	0.0224 (10)	0.0238 (10)	−0.0002 (8)	0.0108 (8)	−0.0005 (8)
C10	0.0280 (11)	0.0368 (12)	0.0335 (12)	0.0073 (9)	0.0071 (9)	0.0005 (10)
C4	0.0252 (11)	0.0490 (15)	0.0417 (13)	−0.0075 (10)	0.0056 (10)	−0.0078 (11)
C8	0.0263 (11)	0.0538 (16)	0.0512 (15)	−0.0093 (10)	0.0214 (11)	−0.0024 (12)
C9	0.0198 (10)	0.0519 (16)	0.0456 (14)	0.0028 (10)	0.0094 (10)	−0.0113 (12)
C7	0.0292 (11)	0.0443 (14)	0.0401 (13)	−0.0043 (10)	0.0167 (10)	0.0092 (11)
C3	0.0188 (11)	0.078 (2)	0.0485 (15)	0.0031 (12)	0.0083 (10)	−0.0018 (14)
C2	0.0288 (12)	0.0694 (19)	0.0582 (17)	0.0176 (12)	0.0168 (12)	−0.0098 (15)
C1	0.0325 (12)	0.0460 (15)	0.0503 (15)	0.0093 (11)	0.0146 (11)	−0.0157 (12)

Geometric parameters (Å, º) top

Fe1—O1W	1.9737 (14)	N7—C12	1.336 (3)
Fe1—N7	2.1041 (17)	N7—N8	1.337 (2)
Fe1—N2	2.1256 (16)	N9—N8	1.312 (3)
Fe1—N6	2.1602 (17)	N5—C6	1.321 (3)
Fe1—N1	2.1708 (18)	C5—C4	1.386 (3)
Fe1—Cl1	2.2308 (7)	C5—C6	1.461 (3)
O1W—H1WA	0.9774	C10—C9	1.385 (3)
O1W—H1WB	0.8241	C10—H10A	0.9300
N6—C7	1.339 (3)	C4—C3	1.377 (4)
N6—C11	1.347 (3)	C4—H4A	0.9300
N2—N3	1.331 (2)	C8—C9	1.366 (4)
N2—C6	1.334 (2)	C8—C7	1.377 (3)
N1—C1	1.340 (3)	C8—H8A	0.9300
N1—C5	1.345 (3)	C9—H9A	0.9300
N4—N3	1.313 (3)	C7—H7A	0.9300
N4—N5	1.348 (3)	C3—C2	1.368 (4)
C11—C10	1.384 (3)	C3—H3A	0.9300
C11—C12	1.461 (3)	C2—C1	1.371 (3)
N10—C12	1.322 (3)	C2—H2A	0.9300
N10—N9	1.345 (3)	C1—H1A	0.9300

O1W—Fe1—N7	164.20 (6)	N8—N9—N10	111.58 (17)
O1W—Fe1—N2	86.71 (6)	N9—N8—N7	107.23 (16)
N7—Fe1—N2	83.89 (7)	C6—N5—N4	103.55 (17)
O1W—Fe1—N6	91.08 (7)	N1—C5—C4	122.2 (2)
N7—Fe1—N6	76.34 (7)	N1—C5—C6	113.45 (17)
N2—Fe1—N6	90.32 (6)	C4—C5—C6	124.4 (2)
O1W—Fe1—N1	93.38 (7)	N5—C6—N2	111.68 (19)
N7—Fe1—N1	96.59 (7)	N5—C6—C5	129.50 (19)
N2—Fe1—N1	75.90 (6)	N2—C6—C5	118.81 (18)
N6—Fe1—N1	165.22 (7)	N10—C12—N7	111.92 (18)
O1W—Fe1—Cl1	94.84 (5)	N10—C12—C11	129.17 (19)
N7—Fe1—Cl1	96.38 (5)	N7—C12—C11	118.91 (18)
N2—Fe1—Cl1	171.26 (5)	C11—C10—C9	118.4 (2)
N6—Fe1—Cl1	98.24 (5)	C11—C10—H10A	120.8
N1—Fe1—Cl1	95.41 (5)	C9—C10—H10A	120.8
Fe1—O1W—H1WA	118.7	C3—C4—C5	118.4 (2)
Fe1—O1W—H1WB	121.3	C3—C4—H4A	120.8
H1WA—O1W—H1WB	119.5	C5—C4—H4A	120.8
C7—N6—C11	118.60 (17)	C9—C8—C7	119.3 (2)
C7—N6—Fe1	125.09 (15)	C9—C8—H8A	120.3
C11—N6—Fe1	116.26 (13)	C7—C8—H8A	120.3
N3—N2—C6	106.24 (16)	C8—C9—C10	119.5 (2)
N3—N2—Fe1	137.95 (13)	C8—C9—H9A	120.2
C6—N2—Fe1	115.30 (13)	C10—C9—H9A	120.2
C1—N1—C5	118.19 (19)	N6—C7—C8	122.1 (2)
C1—N1—Fe1	125.34 (15)	N6—C7—H7A	118.9
C5—N1—Fe1	116.35 (13)	C8—C7—H7A	118.9
N3—N4—N5	111.16 (17)	C2—C3—C4	119.6 (2)
N6—C11—C10	122.05 (19)	C2—C3—H3A	120.2
N6—C11—C12	113.04 (17)	C4—C3—H3A	120.2
C10—C11—C12	124.90 (19)	C3—C2—C1	119.2 (2)
C12—N10—N9	103.34 (17)	C3—C2—H2A	120.4
N4—N3—N2	107.37 (16)	C1—C2—H2A	120.4
C12—N7—N8	105.94 (17)	N1—C1—C2	122.5 (2)
C12—N7—Fe1	115.35 (13)	N1—C1—H1A	118.8
N8—N7—Fe1	138.44 (14)	C2—C1—H1A	118.8

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WA···N4ⁱ	0.98	1.67	2.652 (2)	178
O1W—H1WB···N9ⁱⁱ	0.82	1.80	2.626 (2)	176

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

Experimental details

Crystal data
Chemical formula	[Fe(C₆H₄N₅)₂Cl(H₂O)]
M_r	401.60
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	298
a, b, c (Å)	17.072 (3), 7.1905 (14), 14.292 (3)
β (°)	113.85 (3)
V (Å³)	1604.6 (7)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	1.13
Crystal size (mm)	0.15 × 0.10 × 0.10

Data collection
Diffractometer	Rigaku Mercury2 diffractometer
Absorption correction	Multi-scan (CrystalClear; Rigaku, 2005)
T_min, T_max	0.867, 0.894
No. of measured, independent and observed [I > 2σ(I)] reflections	15693, 3678, 3226
R_int	0.040
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.034, 0.080, 1.13
No. of reflections	3678
No. of parameters	226
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.33, −0.37

Computer programs: CrystalClear (Rigaku, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL/PC (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WA···N4ⁱ	0.98	1.67	2.652 (2)	178.3
O1W—H1WB···N9ⁱⁱ	0.82	1.80	2.626 (2)	175.7

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

Acknowledgements

This work was supported by a start-up grant from Southeast University to Professor Ren-Gen Xiong.

References

Fu, D.-W., Song, Y.-M., Wang, G.-X., Ye, Q., Xiong, R.-G., Akutagawa, T., Nakamura, T., Chan, P. W. H. & Huang, S.-P. (2007). J. Am. Chem. Soc. 129, 5346–5347. Web of Science CSD CrossRef PubMed CAS Google Scholar
Fu, D.-W., Zhang, W. & Xiong, R.-G. (2008). Cryst. Growth Des. 8, 3461–3464. Web of Science CSD CrossRef CAS Google Scholar
Huang, S.-P.-D., Xiong, R.-G., Han, J.-D. & Weiner, B. R. (1999). Inorg. Chim. Acta, 294, 95–98. Web of Science CSD CrossRef CAS Google Scholar
Liu, C.-M., Yu, Z., Xiong, R.-G., Liu, K. & You, X.-Z. (1999). Inorg. Chem. Commun. 2, 31–34. Web of Science CSD CrossRef CAS Google Scholar
Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Xie, Y.-R., Zhao, H., Wang, X.-S., Qu, Z.-R., Xiong, R.-G., Xue, X.-A., Xue, Z.-L. & You, X.-Z. (2003). Eur. J. Inorg. Chem. 20, 3712–3715. Web of Science CSD CrossRef Google Scholar
Zhang, J., Xiong, R.-G., Chen, X.-T., Che, C.-M., Xue, Z.-L. & You, X.-Z. (2001). Organometallics, 20, 4118–4121. Web of Science CSD CrossRef CAS Google Scholar
Zhang, J., Xiong, R.-G., Zuo, J.-L. & You, X.-Z. (2000). Chem. Commun. 16, 1495–1496. Web of Science CSD CrossRef Google Scholar