Poly[μ6-pyridine-2,4-dicarboxyl­ato-barium]

Shuai, Q.; Zhao, X.-N.; Zhao, L.; Hu, F.

doi:10.1107/S1600536810023457

metal-organic compounds

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ISSN: 2056-9890

Volume 66| Part 7| July 2010| Page m832

doi:10.1107/S1600536810023457

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Poly[μ₆-pyridine-2,4-dicarboxylato-barium]

Qi Shuai,^a ^* Xiao-Nong Zhao,^a Li Zhao ^b and Fan Hu ^c

^aCollege of Science, Northwest A&F University, Yangling 712100, Shanxi Province, People's Republic of China, ^bHospital, Northwest A&F University, Yangling 712100, Shanxi Province, People's Republic of China, and ^cStudents Service, Northwest A&F University, Yangling 712100, Shanxi Province, People's Republic of China
^*Correspondence e-mail: shuaiqi@nwsuaf.edu.cn

(Received 10 May 2010; accepted 17 June 2010; online 23 June 2010)

In the title complex, [Ba(C₇H₃NO₄)]_n, the coordination geometry around the Ba^II ion can be described as a distorted bicapped trigonal-prismatic BaNO₇ arrangement. The pyridine-2,4-dicarboxylic acid ligands exhibit a new coordination mode. Adjacent metal centers are linked by the O atoms of the pyridine-2,4-dicarboxylic acid ligands, and then form a three-dimensional supramolecular polymeric framework.

Related literature

For related structures, see: Frisch & Cahill (2006 ); Huang et al. (2007 ); Li et al. (2008 ); Liang et al. (2002 ); Noro et al. (2002 ); Soleimannejad et al. (2009 ); Zhang (2005 ).

Experimental

Crystal data

[Ba(C₇H₃NO₄)]
M_r = 302.44
Monoclinic, C 2/c
a = 11.7570 (11) Å
b = 7.2121 (7) Å
c = 17.4547 (16) Å
β = 93.471 (1)°
V = 1477.3 (2) Å³
Z = 8
Mo Kα radiation
μ = 5.35 mm⁻¹
T = 296 K
0.37 × 0.34 × 0.07 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2002 ) T_min = 0.325, T_max = 0.783
4192 measured reflections
1662 independent reflections
1547 reflections with I > 2σ(I)
R_int = 0.018

Refinement

R[F² > 2σ(F²)] = 0.018
wR(F²) = 0.048
S = 1.03
1662 reflections
119 parameters
H-atom parameters constrained
Δρ_max = 0.70 e Å⁻³
Δρ_min = −0.45 e Å⁻³

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810023457/pb2031sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810023457/pb2031Isup2.hkl

checkCIF report

Comment top

Complex of Sr^II ion with pyridine-2,4-dicarboxylic acid, [Sr(C₇H₃NO₄)(H₂O)₂]_n, has been previously studied (Soleimannejad et al., 2009), which is a two-dimensional polymer.

Here we report a complex (I) assembled by alkaline earth metal Ba^II ion with pyridine-2,4-dicarboxylic acid ligand. The formula for the complex is [Ba(C₇H₃NO₄)]_n, X-ray crystal analyse reveals that the pyridine-2,4-dicarboxylic acid ligands in the complex are completely deprotonated, which is the same with the complex of [Sr(C₇H₃NO₄)(H₂O)₂]_n.

In the title complex, the asymmetric unit consists of one Ba^II ion and one pyridine-2,4-dicarboxylate. The coordination geometry around Ba^II ion (Fig. 1) could be described as a distorted bicapped trigonal prism arrangement with coordination number of 8, where N1, O2B and O4D form the top plane of the trigonal prism, and the bottom plane is completed by O3A, O4E, and O1C, while O1 and O3E capped two quadrilateral faces formed by N1, O3A, O1C, O4D and O2B, O4E, O1C, O4D, respectively. All the coordinated atoms in the title complex are oxygen atoms and nitrogen atoms of pyridine-2,4-dicarboxylic acid ligands, which is different from the complex of [Sr(C₇H₃NO₄)(H₂O)₂]_n, oxygen atoms of water molecules also take part in the coordination with metal centers. The bond length of Ba—O_carboxylate bonds range from 2.706 (2) to 2.8941 (19) Å, which compare well with the mean value determined from the CSD [2.798 (7) Å for Ba—O_carboxylate bond](Table 1). The coordination mode (Fig. 2) of pyridine-2,4-dicarboxylic acid ligands can be classified as µ₆-(κ⁸N, O¹: O¹: O²: O³: O³: O⁴: O⁴), that is, two 4-position carboxylate oxygen atoms (O3 and O4) coordinate to three Ba^II ions, one of the 2-position carboxylate oxygen atoms (O1) coordinates to two Ba^II ions, at the same time, this oxygen atom chelate a Ba^II ion with the pyridyl nitrogen (N1). The other 2-position oxygen atom (O2) coordinates to one Ba^II ion. This coordination mode is not observed in previous reports (Soleimannejad et al., 2009; Huang et al., 2007; Zhang, 2005; Liang et al., 2002; Li et al., 2008; Frisch et al., 2006; Noro et al., 2002). The adjacent metal centers are linked by the oxygen and nitrogen atoms of pyridine-2,4-dicarboxylic acid ligands, and then form a three-dimensional supramolecular polymeric framework (Fig. 3), while in the complex of Sr(C₇H₃NO₄)(H₂O)₂]_n (Soleimannejad et al., 2009), the three-dimensional structure is constructed by non-covalent interactions consisting of O—H···O hydrogen bonds and π-π stacking interactions.

Related literature top

For related structures, see: Frisch & Cahill (2006); Huang et al. (2007); Li et al. (2008); Liang et al. (2002); Noro et al. (2002); Soleimannejad et al. (2009); Zhang (2005).

Experimental top

A mixture of barium chloride dihydrate (0.0244 g, 0.1 mmol), sodium hydroxide (0.0080 g, 0.2 mmol), pyridine-2,4-dicarboxylic acid (0.0167 g, 0.1 mmol), and H₂O (3 mL) was placed in a Parr Teflon-lined stainless stell vessel (25 ml), and then the vessel was sealed and heated at 443.15 K for 4 days. Then the vessel was cooled to 373.15 K at a rate of 5 K h^-1 and slowly cooled to room temperature. Colorless, rectangular single crystals suitable for X-ray diffraction were obtained.

Computing details top

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. Coordination environment of Ba^II ion in the title complex. Non-hydrogen atoms are shown as 30% probability ellipsoids. Hydrogen atoms are omitted for clarity. Symmetry codes: (A) -x + 1, -y, -z + 1; (B) x - 1/2, y + 1/2, z; (C) -x + 1, y, -z + 1/2; (D) -x + 1, -y + 1, -z + 1; (E) x - 1/2, -y + 1/2, z - 1/2.
	Fig. 2. Coordination mode of pyridine-2,4-dicarboxylic acid ligands in the title complex. Non-hydrogen atoms are shown as 30% probability ellipsoids. Hydrogen atoms are omitted for clarity.
	Fig. 3. View of three-dimensional framework along b axis in the title complex.

Poly[µ₆-pyridine-2,4-dicarboxylato-barium] top

Crystal data top

[Ba(C₇H₃NO₄)]	F(000) = 1120
M_r = 302.44	D_x = 2.720 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 2902 reflections
a = 11.7570 (11) Å	θ = 2.3–27.5°
b = 7.2121 (7) Å	µ = 5.35 mm⁻¹
c = 17.4547 (16) Å	T = 296 K
β = 93.471 (1)°	Block, colorless
V = 1477.3 (2) Å³	0.37 × 0.34 × 0.07 mm
Z = 8

Data collection top

Bruker SMART CCD area-detector diffractometer	1662 independent reflections
Radiation source: fine-focus sealed tube	1547 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.018
phi and ω scans	θ_max = 27.5°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Bruker, 2002)	h = −15→13
T_min = 0.325, T_max = 0.783	k = −9→9
4192 measured reflections	l = −16→22

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.018	H-atom parameters constrained
wR(F²) = 0.048	w = 1/[σ²(F_o²) + (0.0287P)² + 1.379P] where P = (F_o² + 2F_c²)/3
S = 1.03	(Δ/σ)_max = 0.002
1662 reflections	Δρ_max = 0.70 e Å⁻³
119 parameters	Δρ_min = −0.45 e Å⁻³
0 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.00237 (13)

Crystal data top

[Ba(C₇H₃NO₄)]	V = 1477.3 (2) Å³
M_r = 302.44	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 11.7570 (11) Å	µ = 5.35 mm⁻¹
b = 7.2121 (7) Å	T = 296 K
c = 17.4547 (16) Å	0.37 × 0.34 × 0.07 mm
β = 93.471 (1)°

Data collection top

Bruker SMART CCD area-detector diffractometer	1662 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2002)	1547 reflections with I > 2σ(I)
T_min = 0.325, T_max = 0.783	R_int = 0.018
4192 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.018	0 restraints
wR(F²) = 0.048	H-atom parameters constrained
S = 1.03	Δρ_max = 0.70 e Å⁻³
1662 reflections	Δρ_min = −0.45 e Å⁻³
119 parameters

Special details top

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.

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 > σ(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
Ba1	0.332689 (13)	0.35356 (2)	0.305017 (8)	0.01561 (9)
N1	0.44887 (19)	0.2899 (3)	0.45739 (13)	0.0175 (5)
O1	0.55983 (18)	0.2658 (3)	0.32482 (11)	0.0282 (5)
O2	0.68945 (17)	0.0756 (3)	0.38112 (12)	0.0260 (4)
O3	0.69395 (18)	0.0151 (3)	0.67349 (12)	0.0255 (4)
O4	0.63043 (17)	0.2757 (3)	0.72435 (11)	0.0214 (4)
C3	0.5531 (2)	0.2109 (4)	0.45821 (15)	0.0151 (5)
C4	0.6129 (2)	0.1626 (3)	0.52576 (17)	0.0179 (6)
H4	0.6828	0.1027	0.5245	0.021*
C5	0.5685 (2)	0.2036 (4)	0.59553 (15)	0.0162 (5)
C6	0.4620 (2)	0.2887 (4)	0.59501 (16)	0.0188 (5)
H6	0.4299	0.3208	0.6406	0.023*
C7	0.4053 (2)	0.3242 (4)	0.52447 (17)	0.0196 (6)
H7	0.3326	0.3749	0.5241	0.023*
C1	0.6053 (2)	0.1797 (4)	0.38175 (17)	0.0190 (6)
C2	0.6353 (2)	0.1607 (3)	0.67076 (16)	0.0169 (6)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ba1	0.01808 (12)	0.01548 (11)	0.01308 (12)	0.00230 (5)	−0.00070 (7)	−0.00040 (5)
N1	0.0179 (11)	0.0184 (11)	0.0159 (11)	0.0011 (9)	−0.0007 (9)	−0.0004 (9)
O1	0.0256 (11)	0.0458 (13)	0.0133 (10)	0.0028 (10)	0.0015 (8)	0.0056 (9)
O2	0.0215 (10)	0.0315 (11)	0.0258 (11)	0.0039 (9)	0.0080 (8)	−0.0055 (9)
O3	0.0332 (11)	0.0187 (10)	0.0231 (11)	0.0011 (9)	−0.0093 (9)	0.0031 (8)
O4	0.0263 (10)	0.0228 (10)	0.0148 (10)	−0.0029 (8)	−0.0006 (8)	−0.0009 (8)
C3	0.0169 (12)	0.0139 (12)	0.0146 (13)	−0.0013 (10)	0.0007 (10)	0.0002 (10)
C4	0.0175 (13)	0.0161 (12)	0.0200 (14)	0.0007 (9)	0.0012 (11)	−0.0003 (10)
C5	0.0187 (13)	0.0135 (11)	0.0160 (13)	−0.0029 (10)	−0.0014 (10)	0.0026 (10)
C6	0.0234 (14)	0.0173 (12)	0.0162 (13)	−0.0002 (11)	0.0037 (10)	−0.0026 (11)
C7	0.0156 (13)	0.0212 (13)	0.0220 (15)	0.0030 (10)	0.0019 (11)	−0.0008 (11)
C1	0.0163 (13)	0.0226 (13)	0.0183 (14)	−0.0041 (11)	0.0027 (10)	−0.0019 (11)
C2	0.0204 (14)	0.0165 (13)	0.0137 (13)	−0.0066 (10)	−0.0003 (11)	0.0039 (10)

Geometric parameters (Å, º) top

Ba1—O3ⁱ	2.706 (2)	O3—Ba1ⁱ	2.706 (2)
Ba1—O2ⁱⁱ	2.727 (2)	O3—Ba1^vii	2.8941 (19)
Ba1—O1ⁱⁱⁱ	2.735 (2)	O4—C2	1.254 (3)
Ba1—O1	2.746 (2)	O4—Ba1^iv	2.762 (2)
Ba1—O4^iv	2.762 (2)	O4—Ba1^vii	2.8463 (19)
Ba1—O4^v	2.8463 (19)	C3—C4	1.380 (4)
Ba1—O3^v	2.8941 (19)	C3—C1	1.519 (4)
Ba1—N1	2.951 (2)	C4—C5	1.385 (4)
Ba1—C2^v	3.199 (3)	C4—H4	0.9300
N1—C7	1.329 (4)	C5—C6	1.394 (4)
N1—C3	1.351 (3)	C5—C2	1.520 (4)
O1—C1	1.263 (3)	C6—C7	1.388 (4)
O1—Ba1ⁱⁱⁱ	2.735 (2)	C6—H6	0.9300
O2—C1	1.242 (3)	C7—H7	0.9300
O2—Ba1^vi	2.727 (2)	C2—Ba1^vii	3.199 (3)
O3—C2	1.256 (3)

O3ⁱ—Ba1—O2ⁱⁱ	115.43 (7)	N1—Ba1—Ba1^ix	132.65 (4)
O3ⁱ—Ba1—O1ⁱⁱⁱ	87.17 (7)	C2^v—Ba1—Ba1^ix	55.55 (4)
O2ⁱⁱ—Ba1—O1ⁱⁱⁱ	150.40 (7)	Ba1^viii—Ba1—Ba1^ix	107.398 (9)
O3ⁱ—Ba1—O1	82.87 (7)	O3ⁱ—Ba1—Ba1ⁱⁱⁱ	99.87 (5)
O2ⁱⁱ—Ba1—O1	134.32 (6)	O2ⁱⁱ—Ba1—Ba1ⁱⁱⁱ	142.45 (5)
O1ⁱⁱⁱ—Ba1—O1	63.66 (7)	O1ⁱⁱⁱ—Ba1—Ba1ⁱⁱⁱ	35.23 (4)
O3ⁱ—Ba1—O4^iv	176.22 (6)	O1—Ba1—Ba1ⁱⁱⁱ	35.07 (4)
O2ⁱⁱ—Ba1—O4^iv	68.31 (6)	O4^iv—Ba1—Ba1ⁱⁱⁱ	76.62 (4)
O1ⁱⁱⁱ—Ba1—O4^iv	89.12 (7)	O4^v—Ba1—Ba1ⁱⁱⁱ	121.12 (4)
O1—Ba1—O4^iv	94.82 (7)	O3^v—Ba1—Ba1ⁱⁱⁱ	97.31 (5)
O3ⁱ—Ba1—O4^v	69.30 (6)	N1—Ba1—Ba1ⁱⁱⁱ	90.91 (5)
O2ⁱⁱ—Ba1—O4^v	84.91 (6)	C2^v—Ba1—Ba1ⁱⁱⁱ	107.64 (5)
O1ⁱⁱⁱ—Ba1—O4^v	85.89 (6)	Ba1^viii—Ba1—Ba1ⁱⁱⁱ	100.719 (6)
O1—Ba1—O4^v	139.80 (6)	Ba1^ix—Ba1—Ba1ⁱⁱⁱ	100.719 (6)
O4^iv—Ba1—O4^v	111.18 (5)	C7—N1—C3	117.8 (2)
O3ⁱ—Ba1—O3^v	111.55 (5)	C7—N1—Ba1	125.67 (17)
O2ⁱⁱ—Ba1—O3^v	81.90 (6)	C3—N1—Ba1	116.43 (17)
O1ⁱⁱⁱ—Ba1—O3^v	71.64 (6)	C1—O1—Ba1ⁱⁱⁱ	124.82 (18)
O1—Ba1—O3^v	132.26 (6)	C1—O1—Ba1	125.07 (18)
O4^iv—Ba1—O3^v	67.86 (5)	Ba1ⁱⁱⁱ—O1—Ba1	109.69 (7)
O4^v—Ba1—O3^v	45.65 (6)	C1—O2—Ba1^vi	151.01 (19)
O3ⁱ—Ba1—N1	76.91 (6)	C2—O3—Ba1ⁱ	139.38 (19)
O2ⁱⁱ—Ba1—N1	85.30 (6)	C2—O3—Ba1^vii	92.19 (16)
O1ⁱⁱⁱ—Ba1—N1	119.93 (6)	Ba1ⁱ—O3—Ba1^vii	106.03 (6)
O1—Ba1—N1	57.12 (6)	C2—O4—Ba1^iv	119.16 (17)
O4^iv—Ba1—N1	104.39 (6)	C2—O4—Ba1^vii	94.48 (17)
O4^v—Ba1—N1	136.23 (6)	Ba1^iv—O4—Ba1^vii	105.85 (6)
O3^v—Ba1—N1	166.82 (6)	N1—C3—C4	122.0 (3)
O3ⁱ—Ba1—C2^v	89.14 (6)	N1—C3—C1	117.9 (2)
O2ⁱⁱ—Ba1—C2^v	86.19 (6)	C4—C3—C1	120.1 (2)
O1ⁱⁱⁱ—Ba1—C2^v	74.73 (7)	C3—C4—C5	119.8 (3)
O1—Ba1—C2^v	137.89 (7)	C3—C4—H4	120.1
O4^iv—Ba1—C2^v	90.59 (6)	C5—C4—H4	120.1
O4^v—Ba1—C2^v	23.01 (7)	C4—C5—C6	118.3 (2)
O3^v—Ba1—C2^v	23.11 (6)	C4—C5—C2	120.9 (2)
N1—Ba1—C2^v	158.59 (7)	C6—C5—C2	120.8 (3)
O3ⁱ—Ba1—Ba1^viii	38.44 (4)	C7—C6—C5	118.0 (3)
O2ⁱⁱ—Ba1—Ba1^viii	114.66 (4)	C7—C6—H6	121.0
O1ⁱⁱⁱ—Ba1—Ba1^viii	70.63 (5)	C5—C6—H6	121.0
O1—Ba1—Ba1^viii	105.21 (5)	N1—C7—C6	123.9 (3)
O4^iv—Ba1—Ba1^viii	140.32 (4)	N1—C7—H7	118.1
O4^v—Ba1—Ba1^viii	36.42 (4)	C6—C7—H7	118.1
O3^v—Ba1—Ba1^viii	73.38 (4)	O2—C1—O1	126.1 (3)
N1—Ba1—Ba1^viii	115.27 (5)	O2—C1—C3	117.5 (3)
C2^v—Ba1—Ba1^viii	51.86 (4)	O1—C1—C3	116.4 (2)
O3ⁱ—Ba1—Ba1^ix	143.17 (4)	O4—C2—O3	125.1 (3)
O2ⁱⁱ—Ba1—Ba1^ix	58.04 (5)	O4—C2—C5	117.7 (2)
O1ⁱⁱⁱ—Ba1—Ba1^ix	92.37 (5)	O3—C2—C5	117.2 (2)
O1—Ba1—Ba1^ix	129.33 (5)	O4—C2—Ba1^vii	62.52 (14)
O4^iv—Ba1—Ba1^ix	37.73 (4)	O3—C2—Ba1^vii	64.71 (14)
O4^v—Ba1—Ba1^ix	73.94 (4)	C5—C2—Ba1^vii	162.39 (18)
O3^v—Ba1—Ba1^ix	35.53 (4)

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

Experimental details

Crystal data
Chemical formula	[Ba(C₇H₃NO₄)]
M_r	302.44
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	296
a, b, c (Å)	11.7570 (11), 7.2121 (7), 17.4547 (16)
β (°)	93.471 (1)
V (Å³)	1477.3 (2)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	5.35
Crystal size (mm)	0.37 × 0.34 × 0.07

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2002)
T_min, T_max	0.325, 0.783
No. of measured, independent and observed [I > 2σ(I)] reflections	4192, 1662, 1547
R_int	0.018
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.018, 0.048, 1.03
No. of reflections	1662
No. of parameters	119
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.70, −0.45

Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

This work was supported by the Scientific Research Foundation of Northwest A&F University (grant No. Z111020828).

References

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