Redetermination of despujolsite, Ca(3)Mn(SO(4))(2)(OH)(6)·3H(2)O.

The crystal structure of despujolsite [tricalcium manganese bis-(sulfate) hexahydroxide tri-hydrate], the Ca/Mn member of the fleischerite group, ideally Ca(3)Mn(4+)(SO(4))(2)(OH)(6)·3H(2)O, was previously determined based on X-ray diffraction intensity data from photographs, without H-atom positions located [Gaudefroy et al. (1968 ▶). Bull. Soc. Fr. Minéral. Crystallogr.91, 43-50]. The current study redetermines the structure of despujolsite from a natural specimen, with all H atoms located and with higher precision. The structure of despujolsite is characterized by layers of CaO(8) polyhedra (m.. symmetry) inter-connected by Mn(OH)(6) octa-hedra (32. symmetry) and SO(4) tetra-hedra (3.. symmetry) along [001]. The average Ca-O, Mn-O and S-O bond lengths are 2.489, 1.915, and 1.472 Å, respectively. There are two distinct hydrogen bonds that stabilize the structural set-up. This work represents the first description of hydrogen bonds in the fleischerite group of minerals.

Related literature

For the previous determination of the despujolsite crystal structure, see: Gaudefroy et al. (1968 ▶). For background to fleischerite, see: Otto (1975 ▶). For the crystal structures of sulfate minerals with split O sites, see: Hill (1977 ▶); Jacobsen et al. (1998 ▶). For TLS (translation, libration, and screw motions) rigid-body analysis, see: Downs (2000 ▶). Parameters for bond-valence analysis were taken from Brese & O’Keeffe (1991 ▶).

Experimental

Crystal data

Ca3Mn(SO4)2(OH)6·3H2O

M = 523.40

Hexagonal,

a = 8.5405 (5) Å

c = 10.8094 (9) Å

V = 682.81 (8) Å3

Z = 2

Mo Kα radiation

μ = 2.49 mm−1

T = 293 K

0.07 × 0.06 × 0.04 mm

Data collection

Bruker APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Sheldrick, 2008a ▶) T min = 0.845, T max = 0.907

6018 measured reflections

871 independent reflections

758 reflections with I > 2σ(I)

R int = 0.051

Refinement

R[F 2 > 2σ(F 2)] = 0.024

wR(F 2) = 0.048

S = 1.06

871 reflections

49 parameters

All H-atom paramters refined

Δρmax = 0.45 e Å−3

Δρmin = −0.30 e Å−3

Absolute structure: Flack (1983 ▶), 305 Friedel pairs

Flack parameter: 0.0 (9)

Data collection: APEX2 (Bruker, 2003 ▶); cell refinement: SAINT (Bruker, 2005 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b ▶); molecular graphics: XtalDraw (Downs & Hall-Wallace, 2003 ▶); software used to prepare material for publication: SHELXTL (Sheldrick, 2008b ▶).

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536811030911/wm2518sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811030911/wm2518Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Ca3Mn(SO4)2(OH)6·3H2O	Dx = 2.546 Mg m−3
Mr = 523.40	Mo Kα radiation, λ = 0.71073 Å
Hexagonal, P62c	Cell parameters from 1145 reflections
Hall symbol: P -6c -2c	θ = 2.8–32.0°
a = 8.5405 (5) Å	µ = 2.49 mm−1
c = 10.8094 (9) Å	T = 293 K
V = 682.81 (8) Å3	Euhedral, yellow
Z = 2	0.07 × 0.06 × 0.04 mm
F(000) = 530

Bruker APEXII CCD area-detector diffractometer	871 independent reflections
Radiation source: fine-focus sealed tube	758 reflections with I > 2σ(I)
graphite	Rint = 0.051
φ and ω scans	θmax = 32.6°, θmin = 2.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 2008a)	h = −12→11
Tmin = 0.845, Tmax = 0.907	k = −12→12
6018 measured reflections	l = −16→15

Refinement on F2	Hydrogen site location: difference Fourier map
Least-squares matrix: full	All H-atom parameters refined
R[F2 > 2σ(F2)] = 0.024	w = 1/[σ2(Fo2) + (0.0113P)2 + 0.2266P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.048	(Δ/σ)max < 0.001
S = 1.06	Δρmax = 0.45 e Å−3
871 reflections	Δρmin = −0.30 e Å−3
49 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraints	Extinction coefficient: 0.0142 (11)
0 constraints	Absolute structure: Flack (1983), 305 Friedel pairs
Primary atom site location: structure-invariant direct methods	Flack parameter: 0.0 (9)
Secondary atom site location: difference Fourier map

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
Mn	0.0000	0.0000	0.0000	0.00846 (12)
Ca	0.1521 (3)	0.30348 (5)	0.2500	0.01085 (10)
S	0.3333	0.6667	0.02544 (5)	0.00936 (12)
O1	0.3333	0.6667	−0.11153 (15)	0.0167 (4)
O2	0.2419 (10)	0.47842 (15)	0.06891 (10)	0.0188 (3)
OH3	0.8945 (8)	0.0966 (8)	0.11070 (10)	0.0109 (3)
OW4	0.5006 (12)	0.4853 (12)	0.2500	0.0171 (5)
H1	0.836 (6)	0.125 (6)	0.076 (2)	0.026 (8)*
H2	0.521 (9)	0.445 (9)	0.193 (2)	0.046 (10)*

	U11	U22	U33	U12	U13	U23
Mn	0.00919 (15)	0.00919 (15)	0.0070 (2)	0.00460 (8)	0.000	0.000
Ca	0.0137 (10)	0.00918 (19)	0.00980 (16)	0.0058 (10)	0.000	0.000
S	0.01001 (16)	0.01001 (16)	0.0081 (2)	0.00501 (8)	0.000	0.000
O1	0.0213 (6)	0.0213 (6)	0.0075 (7)	0.0107 (3)	0.000	0.000
O2	0.027 (3)	0.0106 (5)	0.0170 (5)	0.008 (2)	0.004 (3)	0.0033 (4)
OH3	0.0084 (15)	0.0148 (19)	0.0107 (4)	0.0067 (6)	−0.0006 (16)	−0.0004 (16)
OW4	0.019 (2)	0.023 (2)	0.0136 (6)	0.0138 (12)	0.000	0.000

Mn—OH3i	1.9149 (11)	Ca—OH3viii	2.456 (5)
Mn—OH3ii	1.9149 (11)	Ca—OH3iii	2.518 (5)
Mn—OH3iii	1.9149 (11)	Ca—OH3ix	2.518 (5)
Mn—OH3iv	1.9149 (11)	Ca—OW4	2.578 (9)
Mn—OH3v	1.9149 (11)	Ca—OW4x	2.690 (9)
Mn—OH3vi	1.9149 (11)	S—O2x	1.4697 (11)
Ca—O2vii	2.3465 (11)	S—O2xi	1.4697 (11)
Ca—O2	2.3465 (11)	S—O2	1.4697 (11)
Ca—OH3i	2.456 (5)	S—O1	1.4806 (18)
OH3i—Mn—OH3ii	177.7 (4)	OH3ii—Mn—OH3vi	85.08 (5)
OH3i—Mn—OH3iii	85.08 (5)	OH3iii—Mn—OH3vi	96.5 (3)
OH3ii—Mn—OH3iii	93.4 (3)	OH3iv—Mn—OH3vi	177.7 (4)
OH3i—Mn—OH3iv	85.08 (5)	OH3v—Mn—OH3vi	85.08 (5)
OH3ii—Mn—OH3iv	96.5 (3)	O2x—S—O2xi	110.28 (5)
OH3iii—Mn—OH3iv	85.08 (5)	O2x—S—O2	110.28 (5)
OH3i—Mn—OH3v	96.5 (3)	O2xi—S—O2	110.28 (5)
OH3ii—Mn—OH3v	85.08 (5)	O2x—S—O1	108.65 (5)
OH3iii—Mn—OH3v	177.7 (4)	O2xi—S—O1	108.65 (5)
OH3iv—Mn—OH3v	93.4 (3)	O2—S—O1	108.65 (5)
OH3i—Mn—OH3vi	93.4 (3)

D—H···A	D—H	H···A	D···A	D—H···A
OH3—H1···O2xii	0.75 (2)	2.11 (2)	2.8193 (16)	158 (3)
OW4—H2···O1xiii	0.77 (2)	2.10 (2)	2.7892 (18)	150 (3)

Table 1

Selected bond lengths (Å)

Mn—OH3i	1.9149 (11)
Ca—O2ii	2.3465 (11)
Ca—OH3i	2.456 (5)
Ca—OH3iii	2.518 (5)
Ca—OW4	2.578 (9)
Ca—OW4iv	2.690 (9)
S—O2	1.4697 (11)
S—O1	1.4806 (18)

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) .

Table 2

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
OH3—H1⋯O2v	0.75 (2)	2.11 (2)	2.8193 (16)	158 (3)
OW4—H2⋯O1vi	0.77 (2)	2.10 (2)	2.7892 (18)	150 (3)

Symmetry codes: (v) ; (vi) .