Dimanganese(II) hydroxide vanadate, Mn₂(OH)[VO₄]

Dimanganese(II) hydroxide vanadate was obtained from hydro­thermal reactions. The crystal structure of the title compound is isotypic with that of Zn₂(OH)[VO₄]. Three crystallographically independent Mn²⁺ ions are present, one (site symmetry .m.) with a distorted trigonal-bipyramidal and two (site symmetries .m. and 1) with distorted octa­hedral coordination spheres. These polyhedra are linked through common edges, forming a corrugated layer-type of structure extending parallel to (100). A three-dimensional framework results via additional Mn—O—V—O—Mn connectivities involving the two different tetra­hedral [VO₄] units (each with point-group symmetry .m.). O—H...O hydrogen bonds (one bifurcated) between the OH functions (both with point-group symmetry .m.) and the [VO₄] units complete this arrangement.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](V-O) = 0.003 Å
• R factor = 0.045
• wR factor = 0.062
• Data-to-parameter ratio = 18.6

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          1 Note
              H Mn2 O5 V
PLAT906_ALERT_3_C Large K value in the Analysis of Variance ......     10.197 Check
PLAT975_ALERT_2_C Check Calcd Residual Density  0.65A From      O3       0.65 eA-3
PLAT975_ALERT_2_C Check Calcd Residual Density  0.72A From     O12       0.58 eA-3
PLAT975_ALERT_2_C Check Calcd Residual Density  0.55A From     O23       0.53 eA-3
PLAT975_ALERT_2_C Check Calcd Residual Density  0.92A From     O12       0.47 eA-3
PLAT975_ALERT_2_C Check Calcd Residual Density  0.96A From      O4       0.47 eA-3
PLAT976_ALERT_2_C Check Calcd Residual Density  0.89A From     O13      -0.58 eA-3

Alert level G
PLAT002_ALERT_2_G Number of Distance or Angle Restraints on AtSite          4 Note
PLAT004_ALERT_5_G Polymeric Structure Found with Dimension .......          3 Info
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF     Please Do !
PLAT042_ALERT_1_G Calc. and Reported MoietyFormula Strings  Differ     Please Check
PLAT199_ALERT_1_G Reported _cell_measurement_temperature ..... (K)        293 Check
PLAT200_ALERT_1_G Reported   _diffrn_ambient_temperature ..... (K)        293 Check
PLAT860_ALERT_3_G Number of Least-Squares Restraints .............          2 Note
PLAT910_ALERT_3_G Missing # of FCF Reflections Below Th(Min) .....          2 Why ?
PLAT961_ALERT_5_G Dataset Contains no Negative Intensities .......     Please Check

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   8 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   9 ALERT level G = General information/check it is not something unexpected

   3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   7 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   3 ALERT type 5 Informative message, check

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S1. Comment

Dimanganese hydroxide vanadate, Mn₂(OH)[VO₄], is isotypic with Zn₂(OH)[VO₄] (Wang et al., 1998), Zn_1.86Cd_0.14(OH)[VO₄] (Đorđević et al., 2010) and Cu₂(OH)[VO₄] (Wu et al., 2003). The crystal structure contains three crystallographically independent Mn²⁺-ions (Fig. 1). Mn3 (8d) is located on a general position whereas Mn1 and Mn2 occupy a 4c position each, which is of .m. site symmetry. Mn1 is found in a distorted trigonal-bipyramidal coordination and connects to Mn2 and two Mn3 only via the edges of a single trigonal face. The coordination around Mn2 and Mn3 is octahedral. The former shares four common edges with Mn3 on two trans-faces as well as a single edge with Mn1. Mn3 connects to symmetry-related Mn3 positions via trans-edges along [010] and through edge-sharing to two Mn2 and only one Mn1. From this connectivity corrugated layers parallel to (100) with terminal [Mn1O₅] units result (Fig. 2). Per unit cell two of these layers are present which are linked through Mn—O—V—O—Mn bridges into a three-dimensional framework.

Two [VO₄]^3- units are present. Each V-atom and two O per tetrahedron are located on a mirror plane, whereas one O atom per [VO₄]-unit is found on a general position, respectively. V1 is coordinated by O11 (8d), O12 (4c), and O13 (4c). Mn2 and Mn3 are linked via O11 whereas O13 connects to two Mn3. O12 connects solely to Mn1. However, the second coordination sphere around V2 is dissimilar with respect to O21 (8d) connecting to Mn1–3 and O23 (4c) linked to Mn2 and two Mn3. Again O22 (4c) connects only to Mn1. The two hydroxide groups are of .m. point group symmetry with one straight and one bifurcated O^D···O^A contacts, respectively (Table 1).

Based on the evaluation of the Mn—O—Mn connectivities, the difference in the second coordination sphere between the [V1O₄] and [V2O₄] units, and the dissimilarities found for the two independent hydroxide groups, the more informative structure-related formula should be presented as Mn₄(OH)₂[VO₄]₂ with Z = 4 per unit cell.

It is noteworthy, that for Cu₂(OH)[VO₄] two polymorphs (Pnma and P2₁2₁2₁) were reported by Wu et al. (2003) and Zhang et al. (2014), respectively. We have also repeatedly obtained the acentric modification (hydrothermal conditions at 493 K, pH 9–10, NH₄VO₃ and Cu-acetate or -chloride). Interestingly, Wang et al. (1998) include in a side note that Ni₂(OH)[VO₄] crystallizes in the P2₁2₁2₁ space group as well. Thus, polymorphismn might be related to a size effect or driven by anisotropic magnetic correlations. The latter conjecture is based on the non-magnetic Zn-compound and the "isotropic" S=5/2 spin-system represented by Mn²⁺. For these compounds only the centrosymmetric modification are known up to now.

Related literature

Mn₂(OH)[VO₄] is isotypic with Zn₂(OH)[VO₄] (Wang et al., 1998), Zn_1.86Cd_0.14(OH)[VO₄] (Đorđević et al., 2010), Cu₂(OH)[VO₄] (Wu et al., 2003), but not with the acentric Cu polymorph reported by Zhang et al. (2014).

S2. Experimental

The title compound was obtained as red needle-shaped crystals from reacting H₂V₃O₈ (hydrothermal synthesis, 0.5 mmol V₂O₅ and 0.5 mmol H₂C₂O₄ at 453 K) with 1.75 mmol Mn(acetate)₂^.4H₂O and 5 mmol LiCl in 20 ml of water. Concentrated NH₃-solution was added to adjust the pH to 9.1. The reaction was carried out in a 26 ml Teflon-lined stainless steel autoclave at 493 K for 3 days with subsequent cooling (6 K/h) to room temperature. The final product was washed with distilled water and ethanol alcohol. Source of materials: Mn(acetate)₂^.4H₂O, Sigma; anhydrous H₂C₂O₄, GFS Chemicals; anhydrous LiCl 98+%, Alfa Aesar; V₂O₅, Alfa Aesar; NH₄OH 14.8M, EMD.

S3. Refinement

Hydrogen atom positions were found from difference Fourier maps and were refined by restricting the O—H distance (DFIX 1.0 0.02 O3 H3 O4 H4) and using the ride-on option for the isotropic displacements with U_iso(H) = 1.5 × U_eq(O).

Computing details

Data collection: CrystalClear (Rigaku, 2011); cell refinement: CrystalClear (Rigaku, 2011); data reduction: CrystalClear (Rigaku, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2012); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures

	Fig. 1. A projection of the crystal structure of Mn2(OH)[VO4] along [011]. Displacement ellipsoids are drawn at the 75% probability level.
	Fig. 2. The Mn–Mn connectivity per layer with each connecting line representing a link exclusively via edge-sharing (left). Polyhedral representation for Mn1 (red), Mn2 (yellow) and Mn3 (orange) (right). Displacement ellipsoids are drawn at the 75% probability level.

Dimanganese(II) hydroxide vanadate

Crystal data

Mn2(OH)[VO4]	F(000) = 912
Mr = 241.83	Dx = 3.840 Mg m^−3
Orthorhombic, Pnma	Mo Kα radiation, λ = 0.71075 Å
Hall symbol: -P 2ac 2n	Cell parameters from 18226 reflections
a = 14.9112 (10) Å	θ = 3.3–33.1°
b = 6.1225 (3) Å	µ = 8.04 mm^−1
c = 9.1635 (4) Å	T = 293 K
V = 836.57 (8) Å^3	Needle, red
Z = 8	0.14 × 0.02 × 0.02 mm

Data collection

Rigaku R-AXIS conversion diffractometer	1715 independent reflections
Radiation source: fine-focus sealed tube	1637 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.046
Detector resolution: 10.0000 pixels mm^-1	θmax = 33.1°, θmin = 3.5°
profile data from ω–scans	h = −22→22
Absorption correction: multi-scan (CrystalClear; Rigaku, 2011)	k = −9→9
Tmin = 0.777, Tmax = 1.000	l = −13→14
11657 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.045	Hydrogen site location: difference Fourier map
wR(F^2) = 0.062	H atoms treated by a mixture of independent and constrained refinement
S = 1.36	w = 1/[σ^2(Fo^2) + (0.0121P)^2 + 1.9324P] where P = (Fo^2 + 2Fc^2)/3
1715 reflections	(Δ/σ)max < 0.001
92 parameters	Δρmax = 0.74 e Å^−3
2 restraints	Δρmin = −0.84 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Mn1	0.07126 (4)	0.2500	0.08355 (7)	0.01159 (13)
Mn2	0.28875 (4)	0.2500	0.15984 (6)	0.01046 (12)
Mn3	0.36181 (3)	0.00226 (7)	−0.12336 (5)	0.01003 (9)
V1	0.42573 (4)	0.7500	0.18749 (7)	0.00722 (12)
V2	0.16571 (4)	0.7500	0.02724 (7)	0.00691 (12)
O11	0.37896 (13)	0.5171 (3)	0.1122 (2)	0.0134 (4)
O12	0.0956 (2)	0.2500	−0.1322 (3)	0.0170 (6)
O13	0.46095 (19)	0.2500	−0.1544 (3)	0.0137 (6)
O21	0.17131 (13)	−0.0131 (3)	0.1339 (2)	0.0111 (4)
O22	−0.06661 (19)	0.2500	0.0537 (4)	0.0189 (6)
O23	0.25215 (17)	0.2500	0.3867 (3)	0.0082 (5)
O3	0.27510 (18)	0.2500	−0.0716 (3)	0.0100 (5)
H3	0.2151 (17)	0.2500	−0.110 (5)	0.015*
O4	0.05393 (18)	0.2500	0.3099 (3)	0.0106 (5)
H4	−0.0080 (16)	0.2500	0.341 (5)	0.016*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Mn1	0.0092 (2)	0.0174 (3)	0.0081 (3)	0.000	−0.0003 (2)	0.000
Mn2	0.0112 (3)	0.0121 (3)	0.0080 (2)	0.000	0.0020 (2)	0.000
Mn3	0.01168 (18)	0.00767 (17)	0.01075 (18)	0.00054 (14)	0.00104 (15)	−0.00112 (15)
V1	0.0066 (2)	0.0081 (3)	0.0070 (3)	0.000	0.0004 (2)	0.000
V2	0.0068 (3)	0.0071 (3)	0.0068 (3)	0.000	0.0012 (2)	0.000
O11	0.0142 (9)	0.0143 (9)	0.0116 (9)	−0.0049 (8)	−0.0008 (8)	−0.0010 (8)
O12	0.0171 (14)	0.0240 (16)	0.0100 (13)	0.000	−0.0001 (12)	0.000
O13	0.0081 (12)	0.0102 (12)	0.0228 (15)	0.000	0.0031 (11)	0.000
O21	0.0132 (8)	0.0105 (9)	0.0095 (9)	0.0002 (7)	0.0027 (7)	−0.0017 (7)
O22	0.0096 (12)	0.0270 (17)	0.0201 (15)	0.000	−0.0036 (12)	0.000
O23	0.0087 (11)	0.0092 (12)	0.0067 (11)	0.000	−0.0020 (10)	0.000
O3	0.0095 (11)	0.0093 (12)	0.0113 (12)	0.000	−0.0005 (11)	0.000
O4	0.0087 (12)	0.0112 (13)	0.0118 (13)	0.000	0.0004 (11)	0.000

Geometric parameters (Å, º)

Mn1—O12	2.010 (3)	Mn3—O13	2.137 (2)
Mn1—O22	2.074 (3)	Mn3—O11^i	2.177 (2)
Mn1—O4	2.091 (3)	Mn3—O21^ii	2.2793 (18)
Mn1—O21^i	2.243 (2)	Mn3—O23^ii	2.2981 (19)
Mn1—O21	2.243 (2)	V1—O12^iii	1.683 (3)
Mn2—O3	2.131 (3)	V1—O13^iv	1.717 (3)
Mn2—O23	2.149 (3)	V1—O11	1.731 (2)
Mn2—O11	2.162 (2)	V1—O11^v	1.731 (2)
Mn2—O11^i	2.162 (2)	V2—O22^vi	1.654 (3)
Mn2—O21	2.391 (2)	V2—O21^vii	1.7513 (19)
Mn2—O21^i	2.391 (2)	V2—O21^i	1.7513 (19)
Mn3—O3	2.0487 (18)	V2—O23^viii	1.777 (3)
Mn3—O4^ii	2.0827 (19)
O12—Mn1—O22	92.83 (13)	O21^ii—Mn3—O23^ii	84.16 (8)
O12—Mn1—O4	176.71 (12)	O12^iii—V1—O13^iv	111.06 (15)
O22—Mn1—O4	90.46 (12)	O12^iii—V1—O11	108.39 (9)
O12—Mn1—O21^i	94.73 (8)	O13^iv—V1—O11	109.04 (9)
O22—Mn1—O21^i	133.34 (5)	O12^iii—V1—O11^v	108.39 (9)
O4—Mn1—O21^i	82.99 (7)	O13^iv—V1—O11^v	109.04 (9)
O12—Mn1—O21	94.73 (8)	O11—V1—O11^v	110.93 (14)
O22—Mn1—O21	133.34 (5)	O22^vi—V2—O21^vii	107.05 (9)
O4—Mn1—O21	82.99 (7)	O22^vi—V2—O21^i	107.05 (9)
O21^i—Mn1—O21	91.77 (10)	O21^vii—V2—O21^i	111.86 (13)
O3—Mn2—O23	159.81 (11)	O22^vi—V2—O23^viii	106.89 (15)
O3—Mn2—O11	81.85 (7)	O21^vii—V2—O23^viii	111.82 (8)
O23—Mn2—O11	110.69 (7)	O21^i—V2—O23^viii	111.82 (8)
O3—Mn2—O11^i	81.85 (7)	V1—O11—Mn2	142.49 (11)
O23—Mn2—O11^i	110.69 (7)	V1—O11—Mn3^i	119.19 (10)
O11—Mn2—O11^i	98.30 (11)	Mn2—O11—Mn3^i	94.93 (8)
O3—Mn2—O21	80.28 (7)	V1^viii—O12—Mn1	158.72 (19)
O23—Mn2—O21	84.84 (7)	V1^iv—O13—Mn3	134.78 (5)
O11—Mn2—O21	160.92 (7)	V1^iv—O13—Mn3^i	134.78 (5)
O11^i—Mn2—O21	85.76 (7)	Mn3—O13—Mn3^i	90.43 (11)
O3—Mn2—O21^i	80.28 (7)	V2^ix—O21—Mn1	116.62 (10)
O23—Mn2—O21^i	84.84 (7)	V2^ix—O21—Mn3^x	123.94 (10)
O11—Mn2—O21^i	85.76 (7)	Mn1—O21—Mn3^x	92.06 (7)
O11^i—Mn2—O21^i	160.92 (7)	V2^ix—O21—Mn2	130.42 (10)
O21—Mn2—O21^i	84.69 (10)	Mn1—O21—Mn2	91.37 (7)
O3—Mn3—O4^ii	176.11 (11)	Mn3^x—O21—Mn2	92.42 (7)
O3—Mn3—O13	86.67 (8)	V2^vi—O22—Mn1	160.9 (2)
O4^ii—Mn3—O13	94.01 (8)	V2^iii—O23—Mn2	121.73 (14)
O3—Mn3—O11^i	83.40 (9)	V2^iii—O23—Mn3^x	122.58 (9)
O4^ii—Mn3—O11^i	100.35 (9)	Mn2—O23—Mn3^x	98.57 (9)
O13—Mn3—O11^i	95.13 (10)	V2^iii—O23—Mn3^xi	122.58 (9)
O3—Mn3—O21^ii	93.88 (9)	Mn2—O23—Mn3^xi	98.57 (9)
O4^ii—Mn3—O21^ii	82.29 (9)	Mn3^x—O23—Mn3^xi	84.45 (9)
O13—Mn3—O21^ii	89.97 (10)	Mn3^i—O3—Mn3	95.53 (11)
O11^i—Mn3—O21^ii	174.06 (7)	Mn3^i—O3—Mn2	99.80 (10)
O3—Mn3—O23^ii	91.24 (7)	Mn3—O3—Mn2	99.80 (10)
O4^ii—Mn3—O23^ii	87.68 (7)	Mn3^xi—O4—Mn3^x	95.73 (11)
O13—Mn3—O23^ii	173.63 (10)	Mn3^xi—O4—Mn1	102.51 (10)
O11^i—Mn3—O23^ii	90.60 (9)	Mn3^x—O4—Mn1	102.51 (10)

Symmetry codes: (i) x, −y+1/2, z; (ii) −x+1/2, −y, z−1/2; (iii) −x+1/2, −y+1, z+1/2; (iv) −x+1, −y+1, −z; (v) x, −y+3/2, z; (vi) −x, −y+1, −z; (vii) x, y+1, z; (viii) −x+1/2, −y+1, z−1/2; (ix) x, y−1, z; (x) −x+1/2, −y, z+1/2; (xi) −x+1/2, y+1/2, z+1/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O12	0.96 (2)	1.79 (2)	2.734 (4)	165 (5)
O4—H4···O11^xii	0.97 (2)	2.39 (1)	3.161 (3)	137 (1)
O4—H4···O11^xiii	0.97 (2)	2.39 (1)	3.161 (3)	137 (1)

Symmetry codes: (xii) x−1/2, y, −z+1/2; (xiii) x−1/2, −y+1/2, −z+1/2.