Hg₃Se₃O₁₀, a mercury(II) compound with mixed-valence oxoselenium(IV/VI) anions

The title compound, trimercury(II) bis­[selenite(IV)] selen­ate(VI), contains three crystallographically inequivalent Hg^II cations with coordination numbers of eight (denoted Hg1 and Hg2) and five (denoted Hg3). The corresponding coordination polyhedra around the metal atoms might be described as intermediates between a square antiprism and a triangulated dodecahedron for both Hg1 and Hg2, and a strongly distorted truncated octahedron for Hg3. [HgO_8/2] layers of edge-sharing [HgO₈] polyhedra propagate parallel to the bc plane, and are connected via Se^VIO₄ tetrahedra and [Hg3O₅] polyhedra along the a axis, forming an arrangement with channels propagating parallel to the b axis. The two independent Se^IVO₃ pyramids bridge the Hg atoms, and the non-bonding orbitals of the Se^IV ions protrude into the channels from opposite sides.

Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ATOMS (Dowty, 1998); software used to prepare material for publication: SHELXL97.

Trimercury(II) {bis[selenite(IV)] selenate(VI)}]

Crystal data

Hg3Se3O10	F(000) = 844
Mr = 998.65	Dx = 7.002 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
a = 8.3979 (9) Å	Cell parameters from 981 reflections
b = 5.3327 (6) Å	θ = 5.3–59.7°
c = 11.1482 (12) Å	µ = 60.07 mm^−1
β = 108.422 (2)°	T = 293 K
V = 473.67 (9) Å^3	Fragment, colourless
Z = 2	0.18 × 0.07 × 0.04 mm

Data collection

Siemens SMART CCD area-detector diffractometer	2684 independent reflections
Radiation source: fine-focus sealed tube	2435 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.060
ω scans	θmax = 30.3°, θmin = 1.9°
Absorption correction: numerical (HABITUS; Herrendorf, 1993-97)	h = −11→11
Tmin = 0.064, Tmax = 0.446	k = −7→7
6813 measured reflections	l = −15→15

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	w = 1/[σ^2(Fo^2) + (0.025P)^2] where P = (Fo^2 + 2Fc^2)/3
R[F^2 > 2σ(F^2)] = 0.027	(Δ/σ)max = 0.001
wR(F^2) = 0.060	Δρmax = 1.98 e Å^−3
S = 1.02	Δρmin = −1.51 e Å^−3
2684 reflections	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
146 parameters	Extinction coefficient: 0.0090 (3)
1 restraint	Absolute structure: Flack (1983)
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.015 (11)

Special details

Experimental. The crystal shape was optimized by minimizing the internal R-value of selected reflections (I>20σ(I)) using the program HABITUS (Herrendorf, 1993–97). The habit so derived was used for the numerical absorption correction.

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
Hg1	0.00338 (3)	0.24647 (10)	0.12945 (3)	0.01513 (9)
Hg2	0.00612 (4)	0.25889 (11)	0.62586 (3)	0.01722 (9)
Hg3	0.37438 (4)	0.74340 (19)	0.20835 (3)	0.02385 (10)
Se1	0.26005 (9)	0.2248 (3)	0.96051 (7)	0.01227 (17)
Se2	0.26538 (10)	0.2866 (2)	0.42224 (8)	0.0120 (2)
Se3	0.64667 (9)	0.2506 (4)	0.28524 (7)	0.01271 (15)
O1	0.1017 (8)	0.1229 (12)	0.8322 (6)	0.0187 (14)
O2	0.1144 (9)	0.4039 (12)	0.4812 (7)	0.0191 (14)
O3	0.1562 (8)	0.0649 (12)	0.3169 (6)	0.0176 (14)
O4	0.1604 (9)	0.4619 (11)	0.0134 (7)	0.0159 (14)
O5	0.2287 (9)	0.0004 (13)	0.0601 (7)	0.0242 (17)
O6	0.2451 (10)	0.5265 (14)	0.3179 (8)	0.0293 (18)
O7	0.5236 (8)	0.0632 (12)	0.3330 (6)	0.0197 (14)
O8	0.5272 (9)	0.4256 (13)	0.1660 (6)	0.0214 (14)
O9	0.7470 (9)	0.4314 (13)	0.4004 (7)	0.0238 (15)
O10	0.7704 (9)	0.0820 (12)	0.2280 (6)	0.0227 (15)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Hg1	0.01823 (15)	0.01396 (19)	0.01333 (14)	0.0008 (2)	0.00517 (11)	0.0000 (2)
Hg2	0.02466 (17)	0.01580 (19)	0.01375 (14)	−0.0026 (2)	0.00971 (12)	−0.00090 (18)
Hg3	0.02511 (18)	0.01728 (17)	0.02787 (18)	0.0001 (3)	0.00653 (13)	0.0091 (2)
Se1	0.0129 (3)	0.0120 (4)	0.0121 (3)	−0.0011 (4)	0.0044 (3)	−0.0010 (4)
Se2	0.0118 (4)	0.0130 (5)	0.0108 (3)	−0.0005 (3)	0.0032 (3)	0.0002 (3)
Se3	0.0115 (3)	0.0140 (4)	0.0127 (3)	−0.0004 (6)	0.0039 (3)	−0.0023 (4)
O1	0.023 (3)	0.020 (3)	0.010 (3)	−0.009 (3)	0.003 (3)	−0.001 (2)
O2	0.021 (4)	0.022 (3)	0.019 (3)	0.009 (3)	0.015 (3)	0.007 (3)
O3	0.019 (3)	0.017 (3)	0.014 (3)	−0.004 (3)	0.002 (3)	−0.004 (3)
O4	0.023 (4)	0.011 (3)	0.019 (4)	0.008 (3)	0.014 (3)	0.002 (2)
O5	0.021 (4)	0.022 (4)	0.024 (4)	0.004 (3)	−0.001 (3)	0.007 (3)
O6	0.030 (4)	0.024 (3)	0.041 (5)	0.004 (3)	0.022 (4)	0.019 (3)
O7	0.021 (3)	0.021 (3)	0.022 (4)	−0.004 (3)	0.012 (3)	0.002 (3)
O8	0.019 (4)	0.028 (4)	0.016 (3)	0.004 (3)	0.004 (3)	0.007 (3)
O9	0.026 (4)	0.021 (3)	0.023 (4)	−0.007 (3)	0.005 (3)	−0.011 (3)
O10	0.027 (4)	0.022 (3)	0.023 (4)	0.001 (3)	0.014 (3)	−0.010 (3)

Geometric parameters (Å, º)

Hg1—O1^i	2.287 (6)	Se2—O6	1.702 (7)
Hg1—O3	2.293 (7)	Se2—O3	1.714 (6)
Hg1—O4^ii	2.312 (7)	Se2—O2	1.719 (6)
Hg1—O4	2.411 (7)	Se3—O9	1.613 (7)
Hg1—O5	2.612 (8)	Se3—O7	1.643 (6)
Hg1—O10^iii	2.677 (7)	Se3—O10	1.647 (6)
Hg1—O5^iv	2.738 (8)	Se3—O8	1.674 (7)
Hg1—O6	2.840 (9)	O1—Hg1^vi	2.287 (6)
Hg1—Se1^v	3.2821 (8)	O1—Hg1^i	3.501 (6)
Hg1—Se2	3.3169 (9)	O1—Hg1^xi	3.718 (6)
Hg2—O2	2.226 (6)	O1—Hg3^vi	3.931 (7)
Hg2—O2^vi	2.295 (7)	O2—Hg2^i	2.295 (7)
Hg2—O1	2.301 (6)	O2—Hg2^vi	3.676 (7)
Hg2—O3^i	2.340 (6)	O3—Hg2^vi	2.340 (6)
Hg2—O10^vii	2.686 (7)	O3—Hg3^xii	3.027 (6)
Hg2—O6^vi	2.686 (8)	O3—Hg2^i	4.063 (7)
Hg2—O9^viii	2.796 (7)	O4—Se1^v	1.720 (6)
Hg2—O9^iii	2.906 (8)	O4—Hg1^iv	2.312 (7)
Hg2—Se2^vi	3.3252 (15)	O5—Se1^v	1.709 (7)
Hg2—Se2^i	3.5542 (15)	O5—Hg3^xii	2.197 (7)
Hg3—O5^ix	2.197 (7)	O5—Hg1^ii	2.738 (8)
Hg3—O6	2.201 (7)	O6—Hg2^i	2.686 (7)
Hg3—O8	2.263 (7)	O7—Hg3^xii	2.304 (7)
Hg3—O7^ix	2.304 (7)	O7—Hg2^viii	4.159 (7)
Hg3—O4	2.782 (7)	O8—Hg3^xii	3.935 (7)
Hg3—O3^ix	3.027 (6)	O9—Hg2^vii	2.796 (7)
Hg3—Se3	3.4103 (15)	O9—Hg2^xiii	2.906 (8)
Hg3—Se3^ix	3.4700 (14)	O10—Hg1^xiii	2.677 (7)
Hg3—Se1^x	3.6702 (12)	O10—Hg2^viii	2.686 (7)
Se1—O1	1.705 (6)	O10—Hg3^xii	3.729 (7)
Se1—O5^xi	1.709 (7)	O10—Hg2^vii	4.156 (7)
Se1—O4^xi	1.720 (6)
O1^i—Hg1—O3	109.8 (2)	O1—Hg2—O9^viii	82.6 (2)
O1^i—Hg1—O4^ii	121.6 (2)	O3^i—Hg2—O9^viii	168.3 (2)
O3—Hg1—O4^ii	113.0 (2)	O10^vii—Hg2—O9^viii	93.7 (2)
O1^i—Hg1—O4	89.5 (2)	O6^vi—Hg2—O9^viii	113.5 (2)
O3—Hg1—O4	116.6 (2)	O2—Hg2—O9^iii	68.2 (2)
O4^ii—Hg1—O4	104.50 (16)	O2^vi—Hg2—O9^iii	74.0 (2)
O1^i—Hg1—O5	148.7 (2)	O1—Hg2—O9^iii	153.4 (2)
O3—Hg1—O5	79.0 (2)	O3^i—Hg2—O9^iii	70.9 (2)
O4^ii—Hg1—O5	78.2 (3)	O10^vii—Hg2—O9^iii	120.7 (2)
O4—Hg1—O5	60.69 (19)	O6^vi—Hg2—O9^iii	85.4 (2)
O1^i—Hg1—O10^iii	80.5 (2)	O9^viii—Hg2—O9^iii	118.99 (15)
O3—Hg1—O10^iii	76.0 (2)	O5^ix—Hg3—O6	119.3 (3)
O4^ii—Hg1—O10^iii	73.4 (2)	O5^ix—Hg3—O8	121.9 (3)
O4—Hg1—O10^iii	166.2 (2)	O6—Hg3—O8	97.7 (3)
O5—Hg1—O10^iii	130.4 (2)	O5^ix—Hg3—O7^ix	93.4 (3)
O1^i—Hg1—O5^iv	59.2 (2)	O6—Hg3—O7^ix	108.9 (3)
O3—Hg1—O5^iv	165.8 (2)	O8—Hg3—O7^ix	116.4 (2)
O4^ii—Hg1—O5^iv	70.7 (2)	O5^ix—Hg3—O4	71.3 (2)
O4—Hg1—O5^iv	74.1 (3)	O6—Hg3—O4	80.8 (3)
O5—Hg1—O5^iv	115.18 (14)	O8—Hg3—O4	72.7 (2)
O10^iii—Hg1—O5^iv	92.6 (2)	O7^ix—Hg3—O4	164.7 (2)
O1^i—Hg1—O6	68.2 (2)	O5^ix—Hg3—O3^ix	71.6 (2)
O3—Hg1—O6	59.0 (2)	O6—Hg3—O3^ix	67.0 (2)
O4^ii—Hg1—O6	170.0 (2)	O8—Hg3—O3^ix	164.1 (2)
O4—Hg1—O6	76.2 (2)	O7^ix—Hg3—O3^ix	67.8 (2)
O5—Hg1—O6	93.9 (2)	O4—Hg3—O3^ix	107.15 (18)
O10^iii—Hg1—O6	108.2 (2)	O5^ix—Hg3—O9	155.5 (2)
O5^iv—Hg1—O6	118.6 (2)	O6—Hg3—O9	85.2 (2)
O2—Hg2—O2^vi	97.12 (17)	O8—Hg3—O9	48.2 (2)
O2—Hg2—O1	137.8 (2)	O7^ix—Hg3—O9	77.2 (2)
O2^vi—Hg2—O1	102.5 (2)	O4—Hg3—O9	116.21 (17)
O2—Hg2—O3^i	111.2 (2)	O3^ix—Hg3—O9	123.18 (16)
O2^vi—Hg2—O3^i	121.2 (2)	O1—Se1—O5^xi	94.7 (3)
O1—Hg2—O3^i	89.8 (2)	O1—Se1—O4^xi	100.8 (3)
O2—Hg2—O10^vii	81.3 (2)	O5^xi—Se1—O4^xi	95.8 (3)
O2^vi—Hg2—O10^vii	162.4 (2)	O6—Se2—O3	97.7 (4)
O1—Hg2—O10^vii	68.9 (2)	O6—Se2—O2	93.5 (3)
O3^i—Hg2—O10^vii	75.1 (2)	O3—Se2—O2	102.3 (3)
O2—Hg2—O6^vi	149.4 (3)	O9—Se3—O7	109.2 (3)
O2^vi—Hg2—O6^vi	59.4 (2)	O9—Se3—O10	113.6 (4)
O1—Hg2—O6^vi	70.9 (2)	O7—Se3—O10	109.4 (4)
O3^i—Hg2—O6^vi	71.9 (2)	O9—Se3—O8	109.3 (4)
O10^vii—Hg2—O6^vi	127.2 (2)	O7—Se3—O8	108.4 (3)
O2—Hg2—O9^viii	69.8 (2)	O10—Se3—O8	106.9 (3)
O2^vi—Hg2—O9^viii	69.5 (2)

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