inorganic compounds
MnBa2(HPO4)2(H2PO4)2
aFujian Provincial Key Laboratory of Advanced Materials, Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005, Fujian Province, People's Republic of China
*Correspondence e-mail: jxmi@xmu.edu.cn
Crystals of manganese(II) dibarium bis(hydrogenphosphate) bis(dihydrogenphosphate), MnBa2(HPO4)2(H2PO4)2, were obtained by hydrothermal synthesis. The title compound is isotypic with its CdII and CaII analogues. The structure is built up of an infinite {[Mn(HPO4)2(H2PO4)2]4−}n chain running along [100], which consists of alternate MnO6 octahedra and [PO4] tetrahedra, in which the centrosymmetric MnO6 octahedra share their four equatorial O-atom corners with tetrahedral [PO3(OH)] groups and their two axial apices with tetrahedral [PO2(OH)2] groups. These chains are held together by BaO9 coordination polyhedra, developing into a three-dimensional structure. The O—H⋯O hydrogen bonds additionally stabilize the structural set-up. Due to the ionic radius of Mn2+ being much smaller than those of Ca2+ and Cd2+, this may imply that their adopted structure type has a great tolerance for incorporating various ions and the exploitation of more diverse compounds in the future is encouraged.
Related literature
For background to transition metal phosphates, see: Cheetham et al. (1999); Mao et al. (2000); Mi et al. (2000); Sun et al. (2012); Escobal et al. (1999). For isotypic structures, see: Ben Taher et al. (2001) for CdBa2(HPO4)2(H2PO4)2; Ben Tahar et al. (1999) and Toumi et al. (1997) for CaBa2(HPO4)2(H2PO4)2. For the bond-valence method, see: Brown (2002). For ionic radii, see: Shannon (1976).
Experimental
Crystal data
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Refinement
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Data collection: SMART (Bruker, 2001); cell SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2011) and ATOMS (Dowty, 2004); software used to prepare material for publication: SHELXL97.
Supporting information
10.1107/S1600536812022775/br2203sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536812022775/br2203Isup2.hkl
The title compound, MnBa2(HPO4)2(H2PO4)2 was synthesized by using a hydrothermal method. Typically a mixture of Ba(NO3)2 (1.04 g), Mn(CH3COO)2.4H2O (0.98 g), KBF4 (0.60 g) and H3PO4 (2 ml) with the molar ratio of Ba:Mn:P=2:2:15 was prepared, and transferred into a Teflon-lined stainless-steel autoclave (30 ml in volume), then heated to and held at 463 K for 3 days. Transparent, light pink crystals of the title compound were obtained by filtration, rinsed with distilled water several times, and dried in desiccators. Optical examination and powder X-ray diffraction (PXRD) analyses were used to identify the phases of the solid products.
was used to document the crystal morphologies (Fig. 4). Chemical compositions of selected crystals were examined by use of an Oxford Instruments Energy Dispersive X-ray Spectrometer (EDX), which confirmed the ratio of Mn:Ba:P=1:2:4 from single-crystal data.All hydrogen positions were located from the difference Fourier map and tentatively refined without any restraint. Then a common variable was applied for the
of isotropic atomic displacement parameters (Uiso) of all hydrogen atoms. After the bond distance of O8–H3 became improper, so soft restraints on both Uiso and the bond length (d(O–H) = 0.82 (2) Å) were used for H3 during running the refinement.Data collection: SMART (Bruker, 2001); cell
SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2011) and ATOMS (Dowty, 2004); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).MnBa2(HPO4)2(H2PO4)2 | F(000) = 662 |
Mr = 715.55 | Dx = 3.621 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 3807 reflections |
a = 5.4168 (10) Å | θ = 2.6–28.2° |
b = 10.1048 (19) Å | µ = 7.46 mm−1 |
c = 12.183 (2) Å | T = 173 K |
β = 100.199 (3)° | Prism, light pink |
V = 656.3 (2) Å3 | 0.25 × 0.22 × 0.08 mm |
Z = 2 |
Bruker SMART CCD area-detector diffractometer | 1515 independent reflections |
Radiation source: fine-focus sealed tube | 1491 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.021 |
1265 images,ϕ=0, 90, 180 degree, and Δω=0.3 degree, χ= 54.74 degree scans | θmax = 28.2°, θmin = 2.6° |
Absorption correction: multi-scan (SADABS; Bruker, 2001) | h = −7→7 |
Tmin = 0.257, Tmax = 0.587 | k = −13→8 |
3807 measured reflections | l = −15→13 |
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)] = 0.025 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.075 | All H-atom parameters refined |
S = 1.04 | w = 1/[σ2(Fo2) + (0.053P)2 + 1.2855P] where P = (Fo2 + 2Fc2)/3 |
1515 reflections | (Δ/σ)max < 0.001 |
116 parameters | Δρmax = 0.88 e Å−3 |
1 restraint | Δρmin = −1.03 e Å−3 |
MnBa2(HPO4)2(H2PO4)2 | V = 656.3 (2) Å3 |
Mr = 715.55 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 5.4168 (10) Å | µ = 7.46 mm−1 |
b = 10.1048 (19) Å | T = 173 K |
c = 12.183 (2) Å | 0.25 × 0.22 × 0.08 mm |
β = 100.199 (3)° |
Bruker SMART CCD area-detector diffractometer | 1515 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2001) | 1491 reflections with I > 2σ(I) |
Tmin = 0.257, Tmax = 0.587 | Rint = 0.021 |
3807 measured reflections |
R[F2 > 2σ(F2)] = 0.025 | 1 restraint |
wR(F2) = 0.075 | All H-atom parameters refined |
S = 1.04 | Δρmax = 0.88 e Å−3 |
1515 reflections | Δρmin = −1.03 e Å−3 |
116 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
Ba1 | 0.63461 (4) | 0.35046 (2) | 0.322960 (18) | 0.00907 (12) | |
Mn1 | 0.5000 | 0.0000 | 0.5000 | 0.00694 (18) | |
P1 | 0.91926 (18) | 0.01271 (9) | 0.30714 (8) | 0.0065 (2) | |
P2 | 0.26314 (18) | 0.30069 (10) | 0.55243 (8) | 0.0072 (2) | |
O1 | 0.6833 (5) | 0.0118 (3) | 0.3582 (2) | 0.0111 (6) | |
O2 | 0.8498 (5) | 0.0497 (3) | 0.6203 (2) | 0.0104 (5) | |
O3 | 0.4241 (5) | 0.2178 (3) | 0.4898 (2) | 0.0098 (5) | |
O4 | 0.3420 (5) | 0.3043 (3) | 0.6778 (2) | 0.0121 (6) | |
O5 | 0.8762 (5) | −0.0571 (3) | 0.1943 (2) | 0.0104 (6) | |
O6 | 0.9749 (6) | 0.1640 (3) | 0.2869 (3) | 0.0113 (6) | |
O7 | 0.2616 (5) | 0.4494 (3) | 0.5130 (2) | 0.0103 (5) | |
O8 | −0.0222 (5) | 0.2624 (3) | 0.5203 (2) | 0.0104 (5) | |
H1 | 1.093 (15) | 0.168 (6) | 0.258 (7) | 0.038 (11)* | |
H2 | 0.211 (13) | 0.479 (7) | 0.439 (6) | 0.038 (11)* | |
H3 | −0.065 (13) | 0.197 (5) | 0.550 (5) | 0.038 (11)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Ba1 | 0.00826 (17) | 0.01023 (17) | 0.00887 (16) | −0.00059 (7) | 0.00195 (10) | −0.00110 (7) |
Mn1 | 0.0076 (4) | 0.0059 (4) | 0.0078 (4) | −0.0006 (3) | 0.0029 (3) | −0.0002 (3) |
P1 | 0.0079 (5) | 0.0046 (4) | 0.0074 (4) | 0.0003 (3) | 0.0026 (3) | −0.0002 (3) |
P2 | 0.0083 (5) | 0.0058 (4) | 0.0080 (4) | 0.0005 (3) | 0.0027 (3) | 0.0001 (3) |
O1 | 0.0105 (14) | 0.0141 (14) | 0.0099 (13) | 0.0013 (11) | 0.0047 (11) | 0.0026 (11) |
O2 | 0.0078 (13) | 0.0084 (13) | 0.0140 (13) | 0.0005 (10) | −0.0007 (10) | −0.0007 (10) |
O3 | 0.0120 (14) | 0.0076 (13) | 0.0107 (13) | 0.0008 (10) | 0.0043 (10) | −0.0006 (10) |
O4 | 0.0113 (14) | 0.0143 (16) | 0.0103 (14) | 0.0010 (11) | 0.0007 (11) | 0.0005 (10) |
O5 | 0.0144 (15) | 0.0082 (13) | 0.0087 (12) | 0.0008 (10) | 0.0025 (10) | −0.0018 (10) |
O6 | 0.0145 (16) | 0.0090 (13) | 0.0120 (14) | −0.0006 (10) | 0.0064 (12) | −0.0016 (10) |
O7 | 0.0139 (14) | 0.0050 (12) | 0.0119 (13) | −0.0005 (10) | 0.0016 (11) | −0.0008 (10) |
O8 | 0.0110 (14) | 0.0102 (13) | 0.0104 (13) | −0.0022 (11) | 0.0029 (10) | 0.0036 (10) |
Ba1—O4i | 2.663 (3) | Mn1—O2vi | 2.238 (3) |
Ba1—O6 | 2.726 (3) | Mn1—O3 | 2.238 (3) |
Ba1—O7ii | 2.829 (3) | Mn1—O3vi | 2.238 (3) |
Ba1—O3 | 2.837 (3) | P1—O1 | 1.518 (3) |
Ba1—O5iii | 2.852 (3) | P1—O5 | 1.526 (3) |
Ba1—O5iv | 2.892 (3) | P1—O2vii | 1.534 (3) |
Ba1—O8v | 2.906 (3) | P1—O6 | 1.586 (3) |
Ba1—O1iv | 3.025 (3) | P2—O3 | 1.510 (3) |
Ba1—O2i | 3.081 (3) | P2—O4 | 1.512 (3) |
Mn1—O1vi | 2.142 (3) | P2—O8 | 1.574 (3) |
Mn1—O1 | 2.142 (3) | P2—O7 | 1.577 (3) |
Mn1—O2 | 2.238 (3) | ||
O4i—Ba1—O6 | 80.03 (9) | O1—Mn1—O3 | 90.42 (10) |
O4i—Ba1—O7ii | 155.43 (9) | O2—Mn1—O3 | 86.66 (10) |
O6—Ba1—O7ii | 123.55 (9) | O2vi—Mn1—O3 | 93.34 (10) |
O4i—Ba1—O3 | 86.04 (8) | O1vi—Mn1—O3vi | 90.42 (10) |
O6—Ba1—O3 | 99.08 (9) | O1—Mn1—O3vi | 89.58 (10) |
O7ii—Ba1—O3 | 83.49 (8) | O2—Mn1—O3vi | 93.34 (10) |
O4i—Ba1—O5iii | 126.50 (8) | O2vi—Mn1—O3vi | 86.66 (10) |
O6—Ba1—O5iii | 63.30 (9) | O3—Mn1—O3vi | 180.0 |
O7ii—Ba1—O5iii | 75.33 (8) | O1—P1—O5 | 111.18 (17) |
O3—Ba1—O5iii | 134.74 (8) | O1—P1—O2vii | 114.92 (17) |
O4i—Ba1—O5iv | 72.07 (9) | O5—P1—O2vii | 107.95 (16) |
O6—Ba1—O5iv | 151.29 (9) | O1—P1—O6 | 105.48 (17) |
O7ii—Ba1—O5iv | 83.60 (8) | O5—P1—O6 | 107.96 (17) |
O3—Ba1—O5iv | 72.78 (8) | O2vii—P1—O6 | 109.14 (17) |
O5iii—Ba1—O5iv | 141.11 (11) | O3—P2—O4 | 116.01 (17) |
O4i—Ba1—O8v | 126.01 (9) | O3—P2—O8 | 111.55 (16) |
O6—Ba1—O8v | 64.53 (9) | O4—P2—O8 | 110.27 (16) |
O7ii—Ba1—O8v | 67.45 (8) | O3—P2—O7 | 110.33 (16) |
O3—Ba1—O8v | 62.73 (8) | O4—P2—O7 | 105.67 (18) |
O5iii—Ba1—O8v | 72.22 (8) | O8—P2—O7 | 101.92 (15) |
O5iv—Ba1—O8v | 128.50 (8) | P1—O1—Mn1 | 151.07 (19) |
O4i—Ba1—O1iv | 68.71 (9) | P1—O1—Ba1viii | 96.65 (14) |
O6—Ba1—O1iv | 124.66 (9) | Mn1—O1—Ba1viii | 105.85 (11) |
O7ii—Ba1—O1iv | 98.43 (8) | P1vii—O2—Mn1 | 142.65 (17) |
O3—Ba1—O1iv | 121.91 (8) | P1vii—O2—Ba1ix | 93.35 (13) |
O5iii—Ba1—O1iv | 100.73 (8) | Mn1—O2—Ba1ix | 101.64 (10) |
O5iv—Ba1—O1iv | 50.17 (8) | P2—O3—Mn1 | 129.37 (16) |
O8v—Ba1—O1iv | 165.22 (8) | P2—O3—Ba1 | 116.17 (14) |
O4i—Ba1—O2i | 85.71 (8) | Mn1—O3—Ba1 | 114.29 (11) |
O6—Ba1—O2i | 74.60 (8) | P2—O4—Ba1ix | 133.27 (18) |
O7ii—Ba1—O2i | 106.01 (8) | P1—O5—Ba1x | 102.82 (13) |
O3—Ba1—O2i | 170.38 (8) | P1—O5—Ba1viii | 101.91 (13) |
O5iii—Ba1—O2i | 49.12 (8) | Ba1x—O5—Ba1viii | 141.10 (11) |
O5iv—Ba1—O2i | 109.20 (8) | P1—O6—Ba1 | 119.25 (17) |
O8v—Ba1—O2i | 119.07 (8) | P1—O6—H1 | 108 (5) |
O1iv—Ba1—O2i | 59.06 (8) | Ba1—O6—H1 | 132 (5) |
O1vi—Mn1—O1 | 180.0 | P2—O7—Ba1ii | 118.46 (15) |
O1vi—Mn1—O2 | 86.79 (11) | P2—O7—H2 | 125 (4) |
O1—Mn1—O2 | 93.21 (11) | Ba1ii—O7—H2 | 116 (4) |
O1vi—Mn1—O2vi | 93.21 (11) | P2—O8—Ba1xi | 125.90 (14) |
O1—Mn1—O2vi | 86.79 (11) | P2—O8—H3 | 116 (5) |
O2—Mn1—O2vi | 180.0 | Ba1xi—O8—H3 | 116 (5) |
O1vi—Mn1—O3 | 89.58 (10) |
Symmetry codes: (i) x, −y+1/2, z−1/2; (ii) −x+1, −y+1, −z+1; (iii) −x+2, y+1/2, −z+1/2; (iv) −x+1, y+1/2, −z+1/2; (v) x+1, y, z; (vi) −x+1, −y, −z+1; (vii) −x+2, −y, −z+1; (viii) −x+1, y−1/2, −z+1/2; (ix) x, −y+1/2, z+1/2; (x) −x+2, y−1/2, −z+1/2; (xi) x−1, y, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O6—H1···O4xii | 0.79 (8) | 1.82 (8) | 2.600 (4) | 172 (7) |
O7—H2···O5iv | 0.95 (7) | 1.65 (7) | 2.504 (4) | 149 (6) |
O8—H3···O2xi | 0.80 (2) | 1.82 (2) | 2.623 (4) | 178 (8) |
Symmetry codes: (iv) −x+1, y+1/2, −z+1/2; (xi) x−1, y, z; (xii) x+1, −y+1/2, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | MnBa2(HPO4)2(H2PO4)2 |
Mr | 715.55 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 173 |
a, b, c (Å) | 5.4168 (10), 10.1048 (19), 12.183 (2) |
β (°) | 100.199 (3) |
V (Å3) | 656.3 (2) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 7.46 |
Crystal size (mm) | 0.25 × 0.22 × 0.08 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2001) |
Tmin, Tmax | 0.257, 0.587 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3807, 1515, 1491 |
Rint | 0.021 |
(sin θ/λ)max (Å−1) | 0.665 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.025, 0.075, 1.04 |
No. of reflections | 1515 |
No. of parameters | 116 |
No. of restraints | 1 |
H-atom treatment | All H-atom parameters refined |
Δρmax, Δρmin (e Å−3) | 0.88, −1.03 |
Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2011) and ATOMS (Dowty, 2004).
D—H···A | D—H | H···A | D···A | D—H···A |
O6—H1···O4i | 0.79 (8) | 1.82 (8) | 2.600 (4) | 172 (7) |
O7—H2···O5ii | 0.95 (7) | 1.65 (7) | 2.504 (4) | 149 (6) |
O8—H3···O2iii | 0.80 (2) | 1.82 (2) | 2.623 (4) | 178 (8) |
Symmetry codes: (i) x+1, −y+1/2, z−1/2; (ii) −x+1, y+1/2, −z+1/2; (iii) x−1, y, z. |
Acknowledgements
This work was supported by the National Natural Science Foundation of China (No. 40972035) and the Scientific and Technological Innovation Platform of Fujian Province (No. 2006L2003).
References
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Microporous phosphate materials based on transition metal elements have been extensively studied due to their potential optical, electrical, magnetic, and catalytic properties, as well as some interesting properties which are inaccessible to zeolites and other frameworks based on main-group elements only (Cheetham et al., 1999). As a part of our systematical investigation concerning the synthesis and spectroscopic studies of phosphates with transition metal ions, e.g. V3+, Cr3+, Fe3+ and Co2+ etc. (Mao et al., 2000; Mi et al., 2000; Sun et al., 2012), herein we report the crystal structure of MnBa2(HPO4)2(H2PO4)2, which has been prepared under hydrothermal conditions. To the best of our knowledge, there is very scant information on manganese barium hydroxy-hydrated phosphates. This is the second hydroxy-hydrated phosphate after the compound of Ba(MnPO4)2.H2O (Escobal et al., 1999).
The title compound, MnBa2(HPO4)2(H2PO4)2, is isotypic to its Cd and Ca analogues (Ben Taher et al., 2001; Ben Tahar et al., 1999 & Toumi et al., 1997). In the structure, the asymmetric unit contains one Mn atom, two crystallographically distinct P atoms and one Ba atom (Figs 1–3). Mn1 lies on the inversion center (1/2,0,1/2) (i.e. 2d) and adopts slightly distorted octahedral coordination with an average bond distance of Mn–O = 2.206 Å. The [MnO6] octahedron has six O-corners each fused by corner-sharing to an phosphate tetrahedron, four equatorial O-corners to tetrahedral [PO3(OH)] groups and two axial apices to tetrahedral [PO2(OH)2] groups. P1 is surrounded by three O atoms and one OH group forming a tetrahedral hydrogenphosphate group with an average bond length of P–O = 1.541 Å, while P2 is coordinated to two O atoms and two OH groups forming a tetrahedral dihydrogenphosphate group with d(P–O)av = 1.543 Å. Two hydrogenphosphate [PO3(OH)] groups bridge pairs of vertices from each octahedron via their common O-corners, and vice versa, subsequently to develop into a chain running along the direction of [100], and each side of which is decorated by flanking dihydrogenphosphate [PO2(OH)2] groups (Fig. 2). The infinite {[Mn(HPO4)2(H2PO4)2]4-}n anionic chains are held together by BaO9 coordination spheres, which are composed of barium ions (Ba2+) surrounded by nine adjacent oxygen atoms with an average bond distance of Ba–O = 2.868 Å, developing into a three-dimensional structure (Figs 1,3) The structural set-up is additionally stabilized by O–H···O hydrogen bonds, which occur between [PO3(OH)] and [PO2(OH)2], and form a two-dimensional hydrogen bonding network parallel to the plane of (100). With regard to the [PO3(OH)] groups, one of O-corners bridged to [MnO6] octahedra (i.e. O2) and one non-bridged O-corner (i.e. O5) as well as the OH terminal link individually to their adjacent [PO2(OH)2] groups via hydrogen bonds (i.e. 1 OH donor + 2 acceptors). For [PO2(OH)2] groups, except for O3 connected to a [MnO6] octahedron, O4 and two OH terminals link to three [PO3(OH)] groups via hydrogen bonds (i.e. 2 OH donors + 1 acceptor) (Fig. 1). The connectivity of hydrogen bonds is further confirmed by a bond-valence-sum calculation. The bond-valence-sum calculation shows that the bond valence sums of Ba1, Mn1, P1 and P2 are 1.99, 1.96, 4.76 and 4.73 valence units (v.u.), respectively, while those of oxygen atoms O1, O2, O3, O4, O5, O6, O7 and O8 are -1.79, -1.63, -1.81, -1.65, -1.65, -1.36, -1.31 and -1.27 v.u., respectively (Brown, 2002). Oxygen atoms O6, O7 and O8 with the bond valence sums in the ranges of -1.36 to -1.27 v.u. are protonated for compensating the negative charge (i.e. of hydroxy oxygen atoms). Oxygen atoms O2, O4 and O5 with the bond valence sums of -1.63 to -1.65 u.v. require a hydrogen bond to compensate the negative charge. This is why among three oxygen atoms (O1, O2, O3) which link to [MnO6] octahedra, only O2 is involved in a hydrogen bond. Due to the 6-coordinate effective ionic radius of Mn2+ (0.830 Å, HS) is much smaller than those of Ca2+(1.00 Å) and Cd2+(0.95 Å)(Shannon, 1976), this implies that their adopted structure type has a great tolerance for incorporating various ions and the exploitation on more diverse compounds in the future are encouraged.