supplementary materials


Acta Cryst. (2009). E65, m146-m147    [ doi:10.1107/S1600536808043997 ]

catena-Poly[[[triaqua(nitrato-[kappa]2O,O')neodymium(III)]-bis([mu]2-pyridinium-4-carboxylato-[kappa]2O:O')] bis(perchlorate) monohydrate]

J.-Z. Pu

Abstract top

In the title compound, {[Nd(NO3)(C6H5NO2)2(H2O)3](ClO4)2·H2O}n, the NdIII atom is nine-coordinated by four O atoms from four pyridinium-4-carboxylate ligands, two O atoms from a chelating nitrate anion and three water molecules in a distorted tricapped trigonal-prismatic coordination geometry. Adjacent Nd atoms are linked by the bidentate pyridinium-4-carboxylate ligands into a chain running along the b axis. The chains are further connected by O-H...O and N-H...O hydrogen bonds into a three-dimensional network.

Comment top

In the structural investigation of isonicotinate complexes, it has been found that the isonicotinate functions as a multidentate ligand with versatile binding and coordination modes (Liao et al., 2004; Wang et al., 2004). In this paper, we report the crystal structure of the title compound, a new NdIII complex resulted from the hydrothermal treatment of isonicotinic acid, Nd2O3 and a little nitric acid.

As depicted in Fig. 1, the asymmetric unit consists of one NdIII atom, two pyridinium-4-carboxylate (Hint) ligands, one coordinated nitrate anion, three coordinated water molecules, two perchlorate anions and one uncoordinated water molecule. The NdIII atom is nine-coordinated in a distorted tricapped trigonal prismatic coordination geometry, defined by four O atoms from four different Hint ligands, two O atoms from a nitrate anion and three water molecules (Table 1). The Hint ligands link the metal centres to form a polymeric chain (Fig. 2), in which the NdIII atoms are separated by 5.586 (2) and 5.281 (3) Å. The chains are further self-assembled into a three-dimensional supramolecular network through O—H···O and N—H···O hydrogen bonds (Table 2 and Fig. 3).

Related literature top

For related structures, see: Liao et al. (2004); Wang et al. (2004).

Experimental top

A mixture of Nd2O3 (0.168 g, 0.5 mmol), isonicotinic acid (0.123 g, 1 mmol), HNO3 (0.12 ml) and H2O (10 ml) was placed in a 23 ml Teflon-lined reactor, which was heated to 433 K for 3 d and then cooled to room temperature at a rate of 10 K h-1. The crystals obtained were washed with water and dried in air.

Refinement top

H atoms on C and N atoms were positioned geometrically and treated as riding atoms, with C—H = 0.93 Å and N—H = 0.86 Å and with Uiso(H) = 1.2Ueq(C,N). H atoms of water molecules were located in difference Fourier maps and fixed in refinements, with O—H = 0.84 Å and Uiso(H) = 1.5Ueq(O).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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
[Figure 1] Fig. 1. The asymmetric unit of the title compound, extended to show the Nd coordination. Displacement ellipsoids are drawn at the 30% probability level. H atoms have been omitted for clarity. [Symmetry codes: (i) 1 - x, 1 - y, 1 - z; (ii) 1 - x, -y, 1 - z.]
[Figure 2] Fig. 2. View of the polymeric chain. H atoms, perchlorate anions and uncoordinated water molecules are not shown for clarity.
[Figure 3] Fig. 3. A packing view of the title compound, showing hydrogen bonds (dashed lines).
catena-Poly[[[triaqua(nitrato-κ2O,O')neodymium(III)]- bis(µ2-pyridinium-4-carboxylato-κ2O:O')] bis(perchlorate) monohydrate] top
Crystal data top
[Nd(NO3)(C6H5NO2)2(H2O)3](ClO4)2·H2OZ = 2
Mr = 723.43F(000) = 714
Triclinic, P1Dx = 2.072 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.3962 (7) ÅCell parameters from 8000 reflections
b = 10.1119 (8) Åθ = 1.7–26.0°
c = 14.7229 (12) ŵ = 2.57 mm1
α = 81.663 (1)°T = 273 K
β = 79.601 (1)°Block, colourless
γ = 71.334 (1)°0.32 × 0.26 × 0.20 mm
V = 1159.68 (16) Å3
Data collection top
Bruker APEXII CCD
diffractometer
4073 independent reflections
Radiation source: fine-focus sealed tube3923 reflections with I > 2σ(I)
graphiteRint = 0.017
φ and ω scansθmax = 25.2°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 710
Tmin = 0.459, Tmax = 0.605k = 1112
5967 measured reflectionsl = 1617
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.029Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.077H-atom parameters constrained
S = 0.99 w = 1/[σ2(Fo2) + (0.0448P)2 + 3.0364P]
where P = (Fo2 + 2Fc2)/3
4073 reflections(Δ/σ)max = 0.001
334 parametersΔρmax = 1.00 e Å3
12 restraintsΔρmin = 1.11 e Å3
Crystal data top
[Nd(NO3)(C6H5NO2)2(H2O)3](ClO4)2·H2Oγ = 71.334 (1)°
Mr = 723.43V = 1159.68 (16) Å3
Triclinic, P1Z = 2
a = 8.3962 (7) ÅMo Kα radiation
b = 10.1119 (8) ŵ = 2.57 mm1
c = 14.7229 (12) ÅT = 273 K
α = 81.663 (1)°0.32 × 0.26 × 0.20 mm
β = 79.601 (1)°
Data collection top
Bruker APEXII CCD
diffractometer
4073 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
3923 reflections with I > 2σ(I)
Tmin = 0.459, Tmax = 0.605Rint = 0.017
5967 measured reflectionsθmax = 25.2°
Refinement top
R[F2 > 2σ(F2)] = 0.029H-atom parameters constrained
wR(F2) = 0.077Δρmax = 1.00 e Å3
S = 0.99Δρmin = 1.11 e Å3
4073 reflectionsAbsolute structure: ?
334 parametersFlack parameter: ?
12 restraintsRogers parameter: ?
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.3296 (5)0.6208 (4)0.2806 (3)0.0285 (8)
Cl10.75800 (16)0.47280 (12)0.09482 (8)0.0430 (3)
N10.2205 (6)0.7323 (4)0.1159 (3)0.0493 (11)
H10.18790.76540.06280.059*
Nd10.61497 (2)0.219206 (19)0.462773 (12)0.02175 (9)
O10.4362 (4)0.4217 (3)0.3801 (2)0.0329 (6)
C20.2041 (6)0.5822 (5)0.2522 (3)0.0432 (11)
H20.15740.51680.28860.052*
Cl20.24041 (16)0.02494 (12)0.89509 (8)0.0416 (3)
N20.7879 (5)0.2315 (4)0.8926 (2)0.0364 (8)
H2A0.81570.26430.94670.044*
O20.4255 (4)0.6291 (3)0.4190 (2)0.0406 (7)
C30.1495 (7)0.6428 (6)0.1687 (4)0.0557 (14)
H30.06240.62070.14940.067*
O30.6604 (4)0.0616 (3)0.6047 (2)0.0374 (7)
C40.3394 (7)0.7728 (5)0.1414 (3)0.0440 (11)
H40.38590.83620.10250.053*
N40.9277 (5)0.3174 (4)0.4383 (3)0.0388 (9)
O40.9213 (4)0.1992 (3)0.4802 (3)0.0451 (8)
C50.3937 (6)0.7207 (5)0.2256 (3)0.0380 (10)
H50.47290.75230.24560.046*
O50.7969 (4)0.3949 (3)0.4069 (2)0.0455 (8)
C60.4021 (5)0.5516 (4)0.3681 (3)0.0247 (8)
O61.0567 (5)0.3518 (5)0.4292 (3)0.0688 (12)
C70.6913 (5)0.1202 (4)0.7252 (3)0.0246 (8)
O70.5371 (4)0.1017 (3)0.6025 (2)0.0350 (7)
C80.8138 (6)0.0818 (5)0.7579 (3)0.0336 (9)
H80.86280.01690.72270.040*
O80.8174 (13)0.4411 (6)0.1813 (4)0.152 (4)
C90.8617 (6)0.1400 (5)0.8421 (3)0.0380 (10)
H90.94500.11640.86430.046*
O90.8797 (5)0.3853 (5)0.0322 (3)0.0626 (11)
C100.6734 (6)0.2736 (5)0.8629 (3)0.0376 (10)
H100.62670.33870.89950.045*
O100.7386 (6)0.6160 (4)0.0700 (3)0.0720 (13)
C110.6248 (6)0.2203 (4)0.7777 (3)0.0329 (9)
H110.54750.25130.75530.039*
O110.6059 (8)0.4456 (7)0.1061 (8)0.177 (5)
C120.6247 (5)0.0482 (4)0.6362 (3)0.0256 (8)
O120.1848 (15)0.0322 (7)0.8114 (4)0.197 (5)
O130.1153 (5)0.1236 (5)0.9500 (3)0.0634 (11)
O140.2627 (8)0.1133 (5)0.9314 (4)0.108 (2)
O150.3841 (9)0.0555 (9)0.8782 (10)0.256 (8)
O1W0.3147 (4)0.2628 (4)0.5492 (2)0.0426 (7)
H1W0.23750.29000.51540.064*
H2W0.29270.31210.59380.064*
O2W0.8124 (4)0.0227 (3)0.4206 (2)0.0397 (7)
H4W0.89610.06330.44880.060*
H3W0.75940.07820.41510.060*
O3W0.7472 (4)0.2088 (3)0.2962 (2)0.0430 (8)
H6W0.75050.27620.25600.065*
H5W0.76990.13370.27170.065*
O4W0.2124 (9)0.3371 (7)0.7164 (4)0.123 (2)
H8W0.20540.41830.72700.184*
H7W0.20160.28550.76590.184*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.033 (2)0.0229 (19)0.029 (2)0.0026 (16)0.0122 (17)0.0030 (15)
Cl10.0593 (7)0.0339 (6)0.0312 (5)0.0140 (5)0.0023 (5)0.0009 (4)
N10.065 (3)0.048 (2)0.035 (2)0.011 (2)0.029 (2)0.0090 (18)
Nd10.02726 (13)0.01985 (12)0.02122 (12)0.00926 (8)0.01255 (8)0.00457 (8)
O10.0427 (17)0.0241 (14)0.0348 (15)0.0086 (12)0.0216 (13)0.0045 (12)
C20.050 (3)0.042 (3)0.044 (3)0.018 (2)0.024 (2)0.008 (2)
Cl20.0524 (7)0.0347 (6)0.0369 (6)0.0145 (5)0.0004 (5)0.0050 (4)
N20.041 (2)0.045 (2)0.0238 (17)0.0116 (17)0.0175 (15)0.0086 (15)
O20.065 (2)0.0323 (16)0.0311 (16)0.0156 (15)0.0235 (15)0.0024 (13)
C30.062 (3)0.066 (4)0.052 (3)0.028 (3)0.038 (3)0.011 (3)
O30.058 (2)0.0298 (15)0.0322 (15)0.0202 (14)0.0244 (14)0.0116 (12)
C40.062 (3)0.036 (2)0.030 (2)0.011 (2)0.012 (2)0.0079 (19)
N40.034 (2)0.047 (2)0.040 (2)0.0181 (17)0.0146 (16)0.0039 (17)
O40.0366 (17)0.0373 (17)0.064 (2)0.0136 (14)0.0242 (16)0.0137 (16)
C50.049 (3)0.034 (2)0.032 (2)0.012 (2)0.0127 (19)0.0032 (18)
O50.0405 (18)0.0414 (18)0.059 (2)0.0164 (15)0.0250 (16)0.0149 (15)
C60.0240 (19)0.027 (2)0.0237 (19)0.0069 (15)0.0082 (15)0.0011 (15)
O60.047 (2)0.089 (3)0.086 (3)0.046 (2)0.029 (2)0.029 (2)
C70.0282 (19)0.0228 (18)0.0221 (18)0.0047 (15)0.0090 (15)0.0001 (14)
O70.0481 (18)0.0371 (16)0.0299 (15)0.0207 (14)0.0227 (13)0.0041 (12)
C80.038 (2)0.037 (2)0.032 (2)0.0184 (19)0.0124 (18)0.0051 (17)
O80.310 (11)0.075 (4)0.046 (3)0.008 (5)0.060 (4)0.001 (3)
C90.041 (2)0.046 (3)0.034 (2)0.018 (2)0.0219 (19)0.0064 (19)
O90.056 (2)0.070 (3)0.056 (2)0.003 (2)0.0086 (19)0.027 (2)
C100.046 (3)0.037 (2)0.031 (2)0.018 (2)0.0105 (19)0.0115 (18)
O100.101 (3)0.041 (2)0.057 (2)0.016 (2)0.005 (2)0.0161 (18)
C110.038 (2)0.034 (2)0.031 (2)0.0159 (18)0.0149 (18)0.0057 (17)
O110.071 (4)0.115 (5)0.352 (13)0.052 (4)0.074 (6)0.117 (7)
C120.030 (2)0.0241 (19)0.0229 (18)0.0074 (16)0.0102 (15)0.0022 (15)
O120.367 (14)0.100 (5)0.062 (3)0.058 (6)0.084 (6)0.037 (3)
O130.056 (2)0.072 (3)0.058 (2)0.002 (2)0.0162 (19)0.030 (2)
O140.131 (5)0.053 (3)0.093 (4)0.002 (3)0.023 (3)0.027 (3)
O150.085 (5)0.160 (7)0.55 (2)0.082 (5)0.127 (8)0.224 (11)
O1W0.0390 (17)0.058 (2)0.0377 (17)0.0217 (15)0.0107 (14)0.0038 (15)
O2W0.0407 (17)0.0286 (15)0.0522 (19)0.0082 (13)0.0218 (15)0.0024 (13)
O3W0.056 (2)0.0402 (18)0.0296 (16)0.0151 (15)0.0006 (14)0.0030 (13)
O4W0.143 (6)0.133 (6)0.088 (4)0.048 (5)0.007 (4)0.009 (4)
Geometric parameters (Å, °) top
C1—C21.382 (6)O2—C61.240 (5)
C1—C51.385 (6)O2—Nd1i2.392 (3)
C1—C61.506 (5)C3—H30.9300
Cl1—O111.367 (6)O3—C121.245 (5)
Cl1—O101.405 (4)C4—C51.372 (6)
Cl1—O81.408 (6)C4—H40.9300
Cl1—O91.413 (4)N4—O61.220 (5)
N1—C41.321 (7)N4—O51.250 (5)
N1—C31.324 (7)N4—O41.275 (5)
N1—H10.8600C5—H50.9300
Nd1—O12.428 (3)C7—C111.383 (6)
Nd1—O2i2.392 (3)C7—C81.389 (6)
Nd1—O32.446 (3)C7—C121.512 (5)
Nd1—O42.571 (3)C8—C91.365 (6)
Nd1—O52.651 (3)C8—H80.9300
Nd1—O7ii2.390 (3)C9—H90.9300
Nd1—O1W2.542 (3)C10—C111.371 (6)
Nd1—O2W2.567 (3)C10—H100.9300
Nd1—O3W2.505 (3)C11—H110.9300
O1—C61.245 (5)C12—O71.242 (5)
C2—C31.379 (7)O1W—H1W0.8400
C2—H20.9300O1W—H2W0.8400
Cl2—O151.311 (6)O2W—H4W0.8400
Cl2—O121.379 (6)O2W—H3W0.8400
Cl2—O141.388 (5)O3W—H6W0.8400
Cl2—O131.417 (4)O3W—H5W0.8400
N2—C101.329 (6)O4W—H8W0.8400
N2—C91.339 (6)O4W—H7W0.8400
N2—H2A0.8600
C2—C1—C5119.2 (4)O12—Cl2—O14104.1 (5)
C2—C1—C6120.9 (4)O15—Cl2—O13110.6 (4)
C5—C1—C6119.9 (4)O12—Cl2—O13108.2 (4)
O11—Cl1—O10111.3 (4)O14—Cl2—O13113.7 (3)
O11—Cl1—O8107.8 (6)C10—N2—C9122.9 (4)
O10—Cl1—O8106.1 (3)C10—N2—H2A118.6
O11—Cl1—O9110.7 (4)C9—N2—H2A118.6
O10—Cl1—O9113.1 (3)C6—O2—Nd1i162.7 (3)
O8—Cl1—O9107.4 (4)N1—C3—C2120.4 (5)
C4—N1—C3122.6 (4)N1—C3—H3119.8
C4—N1—H1118.7C2—C3—H3119.8
C3—N1—H1118.7C12—O3—Nd1134.0 (3)
O7ii—Nd1—O2i140.53 (12)N1—C4—C5119.6 (5)
O7ii—Nd1—O181.57 (10)N1—C4—H4120.2
O2i—Nd1—O185.82 (10)C5—C4—H4120.2
O7ii—Nd1—O397.66 (10)O6—N4—O5122.0 (4)
O2i—Nd1—O375.38 (10)O6—N4—O4121.0 (4)
O1—Nd1—O3149.37 (11)O5—N4—O4117.0 (4)
O7ii—Nd1—O3W75.54 (11)N4—O4—Nd198.8 (2)
O2i—Nd1—O3W136.17 (11)C4—C5—C1119.5 (4)
O1—Nd1—O3W74.83 (10)C4—C5—H5120.2
O3—Nd1—O3W134.93 (11)C1—C5—H5120.2
O7ii—Nd1—O1W69.63 (11)N4—O5—Nd195.6 (2)
O2i—Nd1—O1W70.93 (11)O2—C6—O1127.0 (4)
O1—Nd1—O1W73.20 (11)O2—C6—C1116.9 (3)
O3—Nd1—O1W77.83 (11)O1—C6—C1116.1 (3)
O3W—Nd1—O1W135.33 (11)C11—C7—C8119.0 (4)
O7ii—Nd1—O2W70.39 (10)C11—C7—C12120.4 (4)
O2i—Nd1—O2W137.28 (10)C8—C7—C12120.5 (3)
O1—Nd1—O2W135.29 (10)C9—C8—C7119.4 (4)
O3—Nd1—O2W70.71 (10)C9—C8—H8120.3
O3W—Nd1—O2W65.02 (10)C7—C8—H8120.3
O1W—Nd1—O2W124.20 (11)N2—C9—C8119.5 (4)
O7ii—Nd1—O4139.99 (11)N2—C9—H9120.2
O2i—Nd1—O477.38 (12)C8—C9—H9120.2
O1—Nd1—O4122.18 (10)N2—C10—C11119.5 (4)
O3—Nd1—O477.44 (10)N2—C10—H10120.3
O3W—Nd1—O480.43 (12)C11—C10—H10120.3
O1W—Nd1—O4143.71 (11)C10—C11—C7119.6 (4)
O2W—Nd1—O470.58 (10)C10—C11—H11120.2
O7ii—Nd1—O5138.71 (10)C7—C11—H11120.2
O2i—Nd1—O570.41 (12)O7—C12—O3126.1 (3)
O1—Nd1—O573.54 (10)O7—C12—C7117.5 (3)
O3—Nd1—O5120.41 (10)O3—C12—C7116.4 (3)
O3W—Nd1—O566.52 (11)Nd1—O1W—H1W115.1
O1W—Nd1—O5130.00 (11)Nd1—O1W—H2W114.5
O2W—Nd1—O5105.70 (11)H1W—O1W—H2W111.6
O4—Nd1—O548.66 (10)Nd1—O2W—H4W120.0
C6—O1—Nd1140.8 (3)Nd1—O2W—H3W112.9
C3—C2—C1118.4 (5)H4W—O2W—H3W111.4
C3—C2—H2120.8Nd1—O3W—H6W127.8
C1—C2—H2120.8Nd1—O3W—H5W119.0
O15—Cl2—O12107.9 (8)H6W—O3W—H5W111.3
O15—Cl2—O14111.9 (6)H8W—O4W—H7W111.5
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x+1, −y, −z+1.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O4W—H7W···O120.842.593.256 (11)136
O4W—H8W···O5i0.842.523.023 (8)119
O4W—H8W···O8i0.842.042.801 (9)150
O3W—H5W···O12ii0.842.112.945 (7)170
O3W—H6W···O80.842.042.846 (8)162
O2W—H3W···O1Wii0.842.122.900 (5)154
O2W—H4W···O4iii0.842.042.861 (4)167
O1W—H2W···O4W0.841.832.593 (7)150
O1W—H1W···O6iv0.842.042.880 (5)178
N2—H2A···O9iii0.862.513.045 (5)121
N2—H2A···O13v0.862.483.033 (5)123
N2—H2A···O10vi0.862.152.868 (5)141
N1—H1···O13vii0.862.462.994 (6)121
N1—H1···O9viii0.862.462.988 (6)120
N1—H1···O14ix0.862.242.953 (6)140
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x+1, −y, −z+1; (iii) −x+2, −y, −z+1; (iv) x−1, y, z; (v) −x+1, −y, −z+2; (vi) x, y−1, z+1; (vii) −x, −y+1, −z+1; (viii) −x+1, −y+1, −z; (ix) x, y+1, z−1.
Table 1
Selected geometric parameters (Å)
top
Nd1—O12.428 (3)Nd1—O7ii2.390 (3)
Nd1—O2i2.392 (3)Nd1—O1W2.542 (3)
Nd1—O32.446 (3)Nd1—O2W2.567 (3)
Nd1—O42.571 (3)Nd1—O3W2.505 (3)
Nd1—O52.651 (3)
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x+1, −y, −z+1.
Table 2
Hydrogen-bond geometry (Å, °)
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D—H···AD—HH···AD···AD—H···A
O4W—H7W···O120.842.593.256 (11)136
O4W—H8W···O5i0.842.523.023 (8)119
O4W—H8W···O8i0.842.042.801 (9)150
O3W—H5W···O12ii0.842.112.945 (7)170
O3W—H6W···O80.842.042.846 (8)162
O2W—H3W···O1Wii0.842.122.900 (5)154
O2W—H4W···O4iii0.842.042.861 (4)167
O1W—H2W···O4W0.841.832.593 (7)150
O1W—H1W···O6iv0.842.042.880 (5)178
N2—H2A···O9iii0.862.513.045 (5)121
N2—H2A···O13v0.862.483.033 (5)123
N2—H2A···O10vi0.862.152.868 (5)141
N1—H1···O13vii0.862.462.994 (6)121
N1—H1···O9viii0.862.462.988 (6)120
N1—H1···O14ix0.862.242.953 (6)140
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x+1, −y, −z+1; (iii) −x+2, −y, −z+1; (iv) x−1, y, z; (v) −x+1, −y, −z+2; (vi) x, y−1, z+1; (vii) −x, −y+1, −z+1; (viii) −x+1, −y+1, −z; (ix) x, y+1, z−1.
Acknowledgements top

The author acknowledges Zunyi Medical College for supporting this work.

references
References top

Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.

Liao, J.-H., Lai, C.-Y., Ho, C.-D. & Su, C.-T. (2004). Inorg. Chem. Commun. 7, 402–404.

Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.

Wang, C.-M., Chuang, Y.-L., Chuang, S.-T. & Lii, K.-H. (2004). J. Solid State Chem. 177, 2305–2310.