Refinement of pyrobelonite, PbMn^IIVO₄(OH), a member of the descloizite group

Pyrobelonite [lead manganese(II) vanadate(V) hydro­xide], PbMn^IIVO₄(OH), has been refined in space group Pnma. It is isostructural with descloizite, PbZnVO₄(OH). Mn^IIO₄(OH)₂ octahedra share edges to form infinite chains parallel to the b axis. Distorted VO₄ tetrahedra share vertices with the octahedra to form a compact framework, in which voids are occupied by [3+4]-coordinated Pb²⁺ cations. All atoms except O3 are on special positions with site symmetry (Mn) or .m. (remaining atoms).

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](V-O) = 0.004 Å
• R factor = 0.018
• wR factor = 0.047
• Data-to-parameter ratio = 14.6

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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Computing details

Data collection: COLLECT (Nonius, 2001); cell refinement: HKL SCALEPACK (Otwinowski & Minor, 1997); data reduction: HKL DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ATOMS (Shape Software, 1999); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997b).

lead manganese(II) vanadate(V) hydroxide

Crystal data

PbMnVO4(OH)	Dx = 5.828 Mg m^−3
Mr = 394.08	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pnma	Cell parameters from 898 reflections
a = 7.646 (2) Å	θ = 3.5–30.0°
b = 6.179 (1) Å	µ = 42.11 mm^−1
c = 9.507 (2) Å	T = 293 K
V = 449.15 (17) Å^3	Fragment, dark red
Z = 4	0.08 × 0.08 × 0.05 mm
F(000) = 684

Data collection

Nonius KappaCCD diffractometer	714 independent reflections
Radiation source: fine-focus sealed tube	699 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.014
ψ and ω scans	θmax = 30.0°, θmin = 3.4°
Absorption correction: numerical maXus (Mackay et al., 1998)	h = −10→10
Tmin = 0.059, Tmax = 0.125	k = −8→8
1242 measured reflections	l = −13→13

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.018	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.047	w = 1/[σ^2(Fo^2) + (0.024P)^2 + 1.30P] where P = (Fo^2 + 2Fc^2)/3
S = 1.15	(Δ/σ)max < 0.001
714 reflections	Δρmax = 1.26 e Å^−3
49 parameters	Δρmin = −1.80 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0086 (4)

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
Pb	0.13286 (2)	0.2500	0.177529 (19)	0.01086 (11)
Mn	0.0000	0.0000	0.5000	0.00650 (17)
V	0.36513 (9)	0.7500	0.31118 (9)	0.00422 (19)
O1	0.1882 (5)	0.7500	0.4274 (4)	0.0082 (7)
O2	0.5407 (5)	0.7500	0.4133 (4)	0.0178 (8)
O3	0.3728 (3)	0.5128 (5)	0.2099 (3)	0.0103 (5)
OH4	0.1565 (5)	0.2500	0.4244 (4)	0.0072 (7)
H	0.243 (11)	0.2500	0.465 (8)	0.020*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Pb	0.01011 (15)	0.01714 (16)	0.00532 (14)	0.000	0.00006 (5)	0.000
Mn	0.0089 (3)	0.0049 (4)	0.0057 (3)	−0.0007 (3)	0.0002 (2)	0.0008 (2)
V	0.0049 (4)	0.0048 (4)	0.0029 (4)	0.000	0.0012 (2)	0.000
O1	0.0099 (17)	0.0087 (16)	0.0058 (15)	0.000	0.0028 (13)	0.000
O2	0.0083 (16)	0.034 (2)	0.0106 (17)	0.000	−0.0038 (13)	0.000
O3	0.0137 (12)	0.0084 (13)	0.0089 (12)	0.0012 (9)	0.0027 (8)	−0.0011 (11)
OH4	0.0050 (14)	0.0068 (17)	0.0098 (18)	0.000	−0.0031 (12)	0.000

Geometric parameters (Å, º)

Pb—OH4	2.354 (4)	V—Pb^xiv	3.4829 (11)
Pb—O3	2.470 (3)	V—Pb^xv	3.7077 (7)
Pb—O3^i	2.470 (3)	V—Pb^xvi	3.7077 (7)
Pb—O1^ii	2.744 (4)	V—Pb^xvii	3.7833 (7)
Pb—O3^iii	2.781 (3)	O1—Mn^x	2.221 (3)
Pb—O3^iv	2.781 (3)	O1—Mn^xvii	2.221 (3)
Pb—O2^ii	2.841 (4)	O1—Pb^xiv	2.744 (4)
Pb—O2^v	3.2843 (15)	O1—Pb^xvii	3.920 (2)
Pb—O2^iv	3.2843 (15)	O1—Pb^viii	4.487 (4)
Pb—V^ii	3.4829 (11)	O1—Pb^xv	4.701 (3)
Mn—OH4^vi	2.082 (3)	O1—Pb^xvi	4.701 (3)
Mn—OH4	2.082 (3)	O2—Pb^xiv	2.841 (4)
Mn—O1^vii	2.221 (3)	O2—Pb^xvi	3.2843 (15)
Mn—O1^viii	2.221 (3)	O2—Pb^xv	3.2843 (15)
Mn—O3^iii	2.221 (3)	O2—Pb^xviii	4.622 (4)
Mn—O3^ix	2.221 (3)	O3—Mn^xix	2.221 (3)
Mn—Mn^x	3.0895 (5)	O3—Pb^xvi	2.781 (3)
Mn—Mn^xi	3.0895 (5)	O3—Pb^xiv	4.681 (3)
Mn—Pb^vi	3.5801 (6)	OH4—Mn^x	2.082 (3)
Mn—Pb^iv	3.6214 (6)	OH4—Pb^xvi	3.769 (4)
Mn—Pb^xii	3.6214 (6)	OH4—Pb^iv	4.120 (4)
V—O2	1.656 (4)	OH4—Pb^xiv	4.234 (3)
V—O1	1.747 (4)	OH4—Pb^xii	4.234 (3)
V—O3	1.755 (3)	OH4—H	0.77 (9)
V—O3^xiii	1.755 (3)
OH4—Pb—O3	79.55 (10)	O3^iii—Pb—O2^iv	119.80 (9)
OH4—Pb—O3^i	79.55 (10)	O3^iv—Pb—O2^iv	53.02 (9)
O3—Pb—O3^i	82.23 (13)	O2^ii—Pb—O2^iv	70.57 (7)
OH4—Pb—O1^ii	145.68 (13)	O2^v—Pb—O2^iv	140.33 (13)
O3—Pb—O1^ii	74.78 (9)	OH4^vi—Mn—OH4	180.0
O3^i—Pb—O1^ii	74.78 (9)	OH4^vi—Mn—O1^vii	87.92 (10)
OH4—Pb—O3^iii	70.81 (9)	OH4—Mn—O1^vii	92.08 (10)
O3—Pb—O3^iii	150.13 (3)	OH4^vi—Mn—O1^viii	92.08 (10)
O3^i—Pb—O3^iii	95.69 (9)	OH4—Mn—O1^viii	87.92 (10)
O1^ii—Pb—O3^iii	133.63 (8)	O1^vii—Mn—O1^viii	180.0
OH4—Pb—O3^iv	70.81 (9)	OH4^vi—Mn—O3^iii	91.85 (13)
O3—Pb—O3^iv	95.69 (9)	OH4—Mn—O3^iii	88.15 (13)
O3^i—Pb—O3^iv	150.13 (3)	O1^vii—Mn—O3^iii	88.83 (12)
O1^ii—Pb—O3^iv	133.63 (8)	O1^viii—Mn—O3^iii	91.17 (12)
O3^iii—Pb—O3^iv	71.45 (12)	OH4^vi—Mn—O3^ix	88.15 (13)
OH4—Pb—O2^ii	156.57 (12)	OH4—Mn—O3^ix	91.85 (13)
O3—Pb—O2^ii	117.21 (9)	O1^vii—Mn—O3^ix	91.17 (12)
O3^i—Pb—O2^ii	117.21 (9)	O1^viii—Mn—O3^ix	88.83 (12)
O1^ii—Pb—O2^ii	57.75 (12)	O3^iii—Mn—O3^ix	180.0
O3^iii—Pb—O2^ii	90.37 (9)	O2—V—O1	104.9 (2)
O3^iv—Pb—O2^ii	90.37 (9)	O2—V—O3	107.12 (11)
OH4—Pb—O2^v	106.17 (7)	O1—V—O3	111.90 (10)
O3—Pb—O2^v	144.17 (9)	O2—V—O3^xiii	107.12 (11)
O3^i—Pb—O2^v	64.76 (9)	O1—V—O3^xiii	111.90 (10)
O1^ii—Pb—O2^v	83.06 (7)	O3—V—O3^xiii	113.3 (2)
O3^iii—Pb—O2^v	53.02 (9)	Mn—OH4—H	109 (4)
O3^iv—Pb—O2^v	119.80 (9)	Mn^x—OH4—H	109 (4)
O2^ii—Pb—O2^v	70.57 (7)	Pb—OH4—H	125 (6)
OH4—Pb—O2^iv	106.17 (7)	Pb^xvi—OH4—H	46 (6)
O3—Pb—O2^iv	64.76 (9)	Pb^iv—OH4—H	163 (6)
O3^i—Pb—O2^iv	144.17 (10)	Pb^xiv—OH4—H	52 (2)
O1^ii—Pb—O2^iv	83.06 (7)	Pb^xii—OH4—H	52 (2)

Symmetry codes: (i) x, −y+1/2, z; (ii) −x+1/2, −y+1, z−1/2; (iii) x−1/2, −y+1/2, −z+1/2; (iv) x−1/2, y, −z+1/2; (v) x−1/2, y−1, −z+1/2; (vi) −x, −y, −z+1; (vii) x, y−1, z; (viii) −x, −y+1, −z+1; (ix) −x+1/2, y−1/2, z+1/2; (x) −x, y+1/2, −z+1; (xi) −x, y−1/2, −z+1; (xii) −x+1/2, −y, z+1/2; (xiii) x, −y+3/2, z; (xiv) −x+1/2, −y+1, z+1/2; (xv) x+1/2, y+1, −z+1/2; (xvi) x+1/2, y, −z+1/2; (xvii) x, y+1, z; (xviii) −x+1, −y+1, −z+1; (xix) 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
OH4—H···O2^xviii	0.77 (9)	2.02 (9)	2.783 (5)	176 (8)

Symmetry code: (xviii) −x+1, −y+1, −z+1.