Isolierte I₁₀^2--Ringe, ein neues Strukturelement in der Polyiodid-Chemie

The novel compound bis(1,4,7,10-tetraoxa­cyclo­do­decane)­cadmium(II) decaiodide, [Cd(C₈H₁₆O₄)₂]I₁₀, contains the [Cd(12-crown-4)₂]²⁺ complex cation, triiodide ions and iodine mol­ecules. Two triiodide ions and two iodine mol­ecules form isolated twisted I₁₀^2- rings. The geometry of the complex cation is as expected, e.g. d(Cd-O) = 2.366 (4) and 2.394 (4) Å.

Computing details

Data collection: COLLECT (Nonius, 1998); cell refinement: COLLECT (Nonius, 1998); data reduction: DENZO (Otwinowski & Minor 1998); program(s) used to solve structure: SHELXS93 (Sheldrick, 1993); program(s) used to refine structure: SHELXL93 (Sheldrick, 1993); molecular graphics: DIAMOND (Brandenburg, 1998); software used to prepare material for publication: WinGX96 (Farrugia, 1996), PARST95 (Nardelli, 1995), PLATON98 (Spek, 1998), CIFEDIT (Wieczorrek, 1999), ORFFE4 (Busing et al., 1977), LEPAGE (Spek, 1988) maXus (MAC Science Corp. & Nonius, 1998).

Bis-(1,3,5,7-Tetraoxacyclododecan)-cadmium-bis-pentaiodid

Crystal data

[Cd(C8H16O4)2]I10	Dx = 2.959 Mg m^−3
Mr = 1733.82	Melting point: 416 K
Orthorhombic, Fddd	Mo Kα radiation, λ = 0.71070 Å
Hall symbol: -F 2uv 2vw	Cell parameters from 22529 reflections
a = 10.914 (1) Å	θ = 2.2–25.7°
b = 21.758 (1) Å	µ = 8.53 mm^−1
c = 32.774 (1) Å	T = 293 K
V = 7782.7 (8) Å^3	Polyeder, metallic red-black
Z = 8	0.19 × 0.11 × 0.10 mm
F(000) = 6160

Data collection

κ-CCD Nonius diffractometer	1853 independent reflections
Radiation source: fine-focus sealed tube	1728 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.062
Oscillation Mode scans	θmax = 25.7°, θmin = 2.2°
Absorption correction: empirical (using intensity measurements) (SORTAV; Blessing, 1997).	h = −13→13
Tmin = 0.328, Tmax = 0.426	k = −26→23
22529 measured reflections	l = −39→39

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.031	Only H-atom displacement parameters refined
wR(F^2) = 0.063	Calculated w = 1/[σ^2(Fo^2) + 234P] where P = (Fo^2 + 2Fc^2)/3
S = 1.09	(Δ/σ)max = 0.001
1853 reflections	Δρmax = 1.75 e Å^−3
83 parameters	Δρmin = −1.27 e Å^−3
0 restraints	Extinction correction: SHELXL93 (Sheldrick, 1993), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.000191 (7)

Special details

Experimental. Die Strukturlösung mit Direkten Methoden schlug in der hochsymmetrischen Raumgruppe Fddd fehl. Das Strukturmodel konnte in der Raumgruppe P-1 gelöst werden und wurde manuell in die Raumgruppe Fddd transformiert.

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 on F² for ALL reflections except for 0 with very negative F² or flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The observed criterion of F² > σ(F²) is used only for calculating R-factor(obs) 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
I1	0.125	0.34528 (3)	0.125	0.0463 (2)
I2	0.17685 (7)	0.34470 (2)	0.21224 (2)	0.0669 (2)
I3	0.14246 (5)	0.18753 (3)	0.21079 (2)	0.0583 (2)
Cd	0.125	0.125	0.625	0.0274 (2)
O1	0.0585 (4)	0.1882 (2)	0.56946 (13)	0.0406 (10)
C2	0.1620 (10)	0.2149 (4)	0.5481 (2)	0.069 (2)
H2A	0.1335 (10)	0.2493 (4)	0.5318 (2)	0.103 (12)*
H2B	0.1958 (10)	0.1845 (4)	0.5297 (2)	0.103 (12)*
C3	0.2582 (9)	0.2362 (4)	0.5753 (3)	0.071 (3)
H3A	0.3301 (9)	0.2474 (4)	0.5596 (3)	0.103 (12)*
H3B	0.2305 (9)	0.2722 (4)	0.5901 (3)	0.103 (12)*
O4	0.2886 (4)	0.1885 (2)	0.60337 (14)	0.0401 (10)
C5	0.3601 (8)	0.2094 (5)	0.6380 (3)	0.071 (3)
H5A	0.4153 (8)	0.2416 (5)	0.6290 (3)	0.103 (12)*
H5B	0.4095 (8)	0.1755 (5)	0.6479 (3)	0.103 (12)*
C6	0.2854 (9)	0.2327 (5)	0.6713 (3)	0.074 (3)
H6A	0.3361 (9)	0.2396 (5)	0.6952 (3)	0.103 (12)*
H6B	0.2482 (9)	0.2714 (5)	0.6635 (3)	0.103 (12)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
I1	0.0527 (4)	0.0257 (3)	0.0604 (4)	0	−0.0003 (3)	0
I2	0.1031 (5)	0.0432 (3)	0.0543 (3)	−0.0031 (3)	−0.0093 (3)	0.0027 (2)
I3	0.0519 (3)	0.0584 (3)	0.0646 (3)	−0.0102 (2)	−0.0069 (2)	0.0062 (2)
Cd	0.0298 (4)	0.0213 (4)	0.0310 (4)	0	0	0
O1	0.050 (3)	0.033 (2)	0.039 (2)	0.003 (2)	−0.006 (2)	0.005 (2)
C2	0.096 (7)	0.065 (5)	0.046 (4)	−0.018 (5)	−0.003 (4)	0.023 (4)
C3	0.061 (5)	0.070 (6)	0.083 (6)	−0.004 (4)	0.007 (5)	0.042 (5)
O4	0.038 (2)	0.029 (2)	0.053 (3)	−0.004 (2)	0.003 (2)	0.004 (2)
C5	0.051 (5)	0.078 (6)	0.083 (6)	−0.029 (4)	−0.002 (4)	−0.017 (5)
C6	0.079 (6)	0.085 (7)	0.058 (5)	−0.046 (5)	−0.012 (5)	−0.002 (4)

Geometric parameters (Å, º)

I1—I2	2.9145 (5)	Cd—O1^ii	2.394 (4)
I1—I2^i	2.9146 (5)	Cd—O1^iii	2.394 (4)
I2—I3	3.4407 (8)	O1—C6^iv	1.441 (9)
I3—I3^ii	2.7474 (11)	O1—C2	1.450 (10)
Cd—O4^iii	2.366 (4)	C2—C3	1.453 (13)
Cd—O4^ii	2.366 (4)	C3—O4	1.424 (9)
Cd—O4^iv	2.366 (4)	O4—C5	1.450 (10)
Cd—O4	2.366 (4)	C5—C6	1.454 (14)
Cd—O1	2.394 (4)	C6—O1^iv	1.441 (9)
Cd—O1^iv	2.394 (4)
I2···I3^v	4.359 (1)	O1···O4^vi	2.742 (6)
I1···Cd	6.086 (1)	O1···O4^vii	3.156 (6)
Cd···O1	2.394 (4)	O4···O4^viii	3.106 (6)
Cd···O4	2.366 (4)	O1···O1^vii	3.110 (6)
O1···O4	2.746 (6)
I2—I1—I2^i	179.50 (3)	O4—Cd—O1^ii	83.1 (2)
I1—I2—I3	88.26 (2)	O1—Cd—O1^ii	81.0 (2)
I3^ii—I3—I2	178.12 (3)	O1^iv—Cd—O1^ii	144.7 (2)
O4^iii—Cd—O4^ii	108.5 (2)	O4^iii—Cd—O1^iii	70.4 (2)
O4^iii—Cd—O4^iv	145.1 (2)	O4^ii—Cd—O1^iii	70.3 (2)
O4^ii—Cd—O4^iv	82.1 (2)	O4^iv—Cd—O1^iii	83.1 (2)
O4^iii—Cd—O4	82.1 (2)	O4—Cd—O1^iii	142.4 (2)
O4^ii—Cd—O4	145.1 (2)	O1—Cd—O1^iii	144.7 (2)
O4^iv—Cd—O4	108.5 (2)	O1^iv—Cd—O1^iii	81.0 (2)
O4^iii—Cd—O1	142.4 (2)	O1^ii—Cd—O1^iii	109.8 (2)
O4^ii—Cd—O1	83.1 (2)	C6^iv—O1—C2	112.7 (7)
O4^iv—Cd—O1	70.3 (2)	C6^iv—O1—Cd	116.2 (4)
O4—Cd—O1	70.4 (2)	C2—O1—Cd	111.1 (4)
O4^iii—Cd—O1^iv	83.1 (2)	O1—C2—C3	113.2 (6)
O4^ii—Cd—O1^iv	142.4 (2)	O4—C3—C2	109.4 (7)
O4^iv—Cd—O1^iv	70.4 (2)	C3—O4—C5	113.7 (7)
O4—Cd—O1^iv	70.3 (2)	C3—O4—Cd	116.3 (5)
O1—Cd—O1^iv	109.8 (2)	C5—O4—Cd	110.8 (4)
O4^iii—Cd—O1^ii	70.3 (2)	O4—C5—C6	113.3 (7)
O4^ii—Cd—O1^ii	70.4 (2)	O1^iv—C6—C5	108.8 (7)
O4^iv—Cd—O1^ii	142.4 (2)
I2^i—I1—I2—I3	−6.10 (2)	C2—C3—O4—C5	−165.2 (7)
I1—I2—I3—I3^ii	−103.5 (5)	C2—C3—O4—Cd	−34.8 (9)
O4^iii—Cd—O1—C6^iv	−160.3 (6)	O4^iii—Cd—O4—C3	164.3 (6)
O4^ii—Cd—O1—C6^iv	88.2 (6)	O4^ii—Cd—O4—C3	53.2 (6)
O4^iv—Cd—O1—C6^iv	4.2 (6)	O4^iv—Cd—O4—C3	−49.9 (5)
O4—Cd—O1—C6^iv	−114.8 (6)	O1—Cd—O4—C3	10.4 (6)
O1^iv—Cd—O1—C6^iv	−55.4 (6)	O1^iv—Cd—O4—C3	−110.2 (6)
O1^ii—Cd—O1—C6^iv	159.4 (6)	O1^ii—Cd—O4—C3	93.3 (6)
O1^iii—Cd—O1—C6^iv	47.5 (6)	O1^iii—Cd—O4—C3	−152.9 (5)
O4^iii—Cd—O1—C2	−29.6 (6)	O4^iii—Cd—O4—C5	−63.8 (5)
O4^ii—Cd—O1—C2	−141.1 (5)	O4^ii—Cd—O4—C5	−175.0 (5)
O4^iv—Cd—O1—C2	134.9 (5)	O4^iv—Cd—O4—C5	82.0 (5)
O4—Cd—O1—C2	15.9 (5)	O1—Cd—O4—C5	142.2 (5)
O1^iv—Cd—O1—C2	75.3 (5)	O1^iv—Cd—O4—C5	21.6 (5)
O1^ii—Cd—O1—C2	−69.9 (5)	O1^ii—Cd—O4—C5	−134.8 (5)
O1^iii—Cd—O1—C2	178.2 (5)	O1^iii—Cd—O4—C5	−21.1 (6)
C6^iv—O1—C2—C3	91.3 (9)	C3—O4—C5—C6	86.1 (9)
Cd—O1—C2—C3	−41.2 (9)	Cd—O4—C5—C6	−47.1 (9)
O1—C2—C3—O4	50.4 (10)	O4—C5—C6—O1^iv	50.2 (11)

Symmetry codes: (i) −x+1/4, y, −z+1/4; (ii) −x+1/4, −y+1/4, z; (iii) x, −y+1/4, −z+5/4; (iv) −x+1/4, y, −z+5/4; (v) x, y+1/2, z+1/2; (vi) −x+3/4, y, −z+7/4; (vii) x, −y+3/4, −z+3/4; (viii) −x+3/4, −y+3/4, z+1.