Absence of halogen...halogen interactions in chlorotrimethylsilane polymorphs

The structures of in situ pressure-frozen chlorotrimethylsilane crystals, (CH₃)₃SiCl, have been determined at 0.23, 0.30 and 0.58 GPa. The molecular arrangements in the low-temperature and high-pressure phases are two-dimensionally isostructural, but different in the third perpendicular direction. Consequently, a striking similarity exists between the unit-cell dimensions of these polymorphs. The absence of short Cl...Cl contacts, both in the low-temperature or pressure-frozen phases of (CH₃)₃SiCl, has been rationalized in terms of the favoured packing patterns and comparable energies of halogen...halogen interactions and other van der Waals forces.

Computing details

For all compounds, data collection: CrysAlis (Oxford Diffraction, 2004); cell refinement: CrysAlis (Oxford Diffraction, 2004); data reduction: CrysAlis (Oxford Diffraction, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP (Siemens, 1990); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures

(tmcs1) chlorotrimethylsilane

Crystal data

C3H9ClSi	Dx = 1.153 Mg m^−3
Mr = 108.64	Melting point: 215 K
Orthorhombic, Pmn21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac -2	Cell parameters from 839 reflections
a = 7.785 (2) Å	θ = 4.2–27.4°
b = 6.43 (3) Å	µ = 0.66 mm^−1
c = 6.254 (3) Å	T = 293 K
V = 313.0 (15) Å^3	Disc, colourless
Z = 2	0.46 × 0.46 × 0.18 × 0.23 (radius) mm
F(000) = 116

Data collection

Kuma KM4CCD κ geometry diffractometer	194 independent reflections
Radiation source: fine-focus sealed tube	170 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.075
ω scans	θmax = 27.4°, θmin = 4.2°
Absorption correction: analytical Katrusiak, A. (2003). REDSHADE - Program for correcting reflections intensities for DAC absorption, gasket shadowing and sample crystal absorption. Adam Mickiewicz University, Poznań. Katrusiak, A. (2004). Z. Kristallogr. 219, 461-467	h = −10→10
Tmin = 0.41, Tmax = 0.94	k = −1→1
1793 measured reflections	l = −8→8

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F^2 > 2σ(F^2)] = 0.032	w = 1/[σ^2(Fo^2) + (0.0568P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.083	(Δ/σ)max < 0.001
S = 1.01	Δρmax = 0.08 e Å^−3
194 reflections	Δρmin = −0.11 e Å^−3
29 parameters	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
1 restraint	Extinction coefficient: 0.19 (3)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack H D (1983), Acta Cryst. A39, 876-881
Secondary atom site location: difference Fourier map	Absolute structure parameter: 0.6 (3)

Special details

Experimental. High-pressure measurement at 0.23 GPa.

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	Occ. (<1)
Cl1	0.0000	0.361 (2)	0.4727 (5)	0.153 (13)
Si1	0.0000	0.6592 (17)	0.3753 (2)	0.0402 (7)*
C1	0.0000	0.699 (4)	0.0771 (13)	0.06 (2)
H11	0.0000	0.8453	0.0461	0.068*
H12	−0.1007	0.6360	0.0166	0.068*	0.50
H12A	0.1007	0.6360	0.0166	0.068*	0.50
C2	0.1922 (9)	0.826 (6)	0.4857 (11)	0.07 (2)
H21	0.2703	0.7133	0.4556	0.089*
H22	0.1765	0.8379	0.6377	0.089*
H23	0.2385	0.9517	0.4311	0.089*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.086 (2)	0.28 (4)	0.088 (2)	0.000	0.000	−0.011 (5)
C1	0.061 (4)	0.05 (7)	0.059 (4)	0.000	0.000	0.046 (13)
C2	0.068 (4)	0.08 (6)	0.077 (4)	−0.026 (8)	−0.011 (3)	−0.045 (10)

Geometric parameters (Å, º)

Cl1—Si1	2.010 (15)	Si1—C2	1.964 (19)
Si1—C1	1.882 (9)	Si1—C2^i	1.964 (19)
C1—Si1—C2	105.9 (7)	C1—Si1—Cl1	115.4 (10)
C1—Si1—C2^i	105.9 (7)	C2—Si1—Cl1	114.3 (10)
C2—Si1—C2^i	99.3 (16)	C2^i—Si1—Cl1	114.3 (10)

Symmetry code: (i) −x, y, z.

(tmcs2) chlorotrimethylsilane

Crystal data

C3H9ClSi	Dx = 1.160 Mg m^−3
Mr = 108.64	Melting point: 215 K
Orthorhombic, Pmn21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac -2	Cell parameters from 989 reflections
a = 7.768 (2) Å	θ = 4.2–22.5°
b = 6.42 (2) Å	µ = 0.66 mm^−1
c = 6.233 (2) Å	T = 293 K
V = 311.0 (11) Å^3	Disc, colourless
Z = 2	0.44 × 0.44 × 0.18 × 0.22 (radius) mm
F(000) = 116

Data collection

Kuma KM4CCD κ geometry diffractometer	164 independent reflections
Radiation source: fine-focus sealed tube	158 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.057
ω scans	θmax = 22.5°, θmin = 4.2°
Absorption correction: analytical Katrusiak, A. (2003). REDSHADE - Program for correcting reflections intensities for DAC absorption, gasket shadowing and sample crystal absorption. Adam Mickiewicz University, Poznań. Katrusiak, A. (2004). Z. Kristallogr. 219, 461-467	h = −8→8
Tmin = 0.40, Tmax = 0.94	k = −2→2
1473 measured reflections	l = −6→6

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F^2 > 2σ(F^2)] = 0.032	w = 1/[σ^2(Fo^2) + (0.0448P)^2 + 0.0802P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.082	(Δ/σ)max = 0.223
S = 1.22	Δρmax = 0.11 e Å^−3
164 reflections	Δρmin = −0.09 e Å^−3
32 parameters	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
1 restraint	Extinction coefficient: 0.018 (17)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack H D (1983), Acta Cryst. A39, 876-881
Secondary atom site location: difference Fourier map	Absolute structure parameter: 0.2 (4)

Special details

Experimental. High-pressure measurement at 0.3 GPa.

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	Occ. (<1)
Cl1	0.0000	0.393 (2)	0.4611 (5)	0.087 (10)
Si1	0.0000	0.693 (2)	0.3624 (4)	0.072 (7)
C1	0.0000	0.700 (4)	0.0724 (15)	0.034 (16)
H11	0.0000	0.8417	0.0247	0.041*
H12	−0.1009	0.6304	0.0193	0.041*	0.50
H12A	0.1009	0.6304	0.0193	0.041*	0.50
C2	0.1988 (13)	0.815 (4)	0.4743 (18)	0.095 (15)
H21	0.2972	0.7648	0.3974	0.114*
H22	0.2115	0.7849	0.6241	0.114*
H23	0.1898	0.9618	0.4551	0.114*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0707 (19)	0.11 (3)	0.081 (2)	0.000	0.000	−0.004 (8)
Si1	0.0462 (16)	0.13 (2)	0.0433 (17)	0.000	0.000	0.016 (5)
C1	0.049 (5)	0.00 (5)	0.053 (5)	0.000	0.000	0.002 (12)
C2	0.072 (5)	0.16 (5)	0.054 (4)	−0.014 (10)	−0.013 (4)	0.016 (11)

Geometric parameters (Å, º)

Cl1—Si1	2.02 (2)	Si1—C2	1.869 (15)
Si1—C1	1.808 (10)	Si1—C2^i	1.869 (15)
C1—Si1—C2	111.3 (5)	C1—Si1—Cl1	109.2 (10)
C1—Si1—C2^i	111.3 (5)	C2—Si1—Cl1	106.8 (7)
C2—Si1—C2^i	111.4 (14)	C2^i—Si1—Cl1	106.8 (7)

Symmetry code: (i) −x, y, z.

(tmcs3) chlorotrimethylsilane

Crystal data

C3H9ClSi	Dx = 1.205 Mg m^−3
Mr = 108.64	Melting point: 215 K
Orthorhombic, Pmn21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac -2	Cell parameters from 798 reflections
a = 7.668 (2) Å	θ = 4.2–24.9°
b = 6.34 (2) Å	µ = 0.69 mm^−1
c = 6.159 (2) Å	T = 293 K
V = 299.4 (11) Å^3	Disc, colourless
Z = 2	0.42 × 0.42 × 0.18 × 0.21 (radius) mm
F(000) = 116

Data collection

Kuma KM4CCD κ geometry diffractometer	199 independent reflections
Radiation source: fine-focus sealed tube	193 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.060
ω scans	θmax = 24.9°, θmin = 4.2°
Absorption correction: analytical Katrusiak, A. (2003). REDSHADE - Program for correcting reflections intensities for DAC absorption, gasket shadowing and sample crystal absorption. Adam Mickiewicz University, Poznań. Katrusiak, A. (2004). Z. Kristallogr. 219, 461-467	h = −9→9
Tmin = 0.41, Tmax = 0.92	k = −2→2
1697 measured reflections	l = −7→7

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F^2 > 2σ(F^2)] = 0.039	w = 1/[σ^2(Fo^2) + (0.0395P)^2 + 0.1814P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.092	(Δ/σ)max < 0.001
S = 1.27	Δρmax = 0.17 e Å^−3
199 reflections	Δρmin = −0.19 e Å^−3
29 parameters	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
1 restraint	Extinction coefficient: 0.031 (17)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack H D (1983), Acta Cryst. A39, 876-881
Secondary atom site location: difference Fourier map	Absolute structure parameter: 0.0 (4)

Special details

Experimental. High-pressure measurement at 0.58 GPa.

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	Occ. (<1)
Cl1	0.0000	0.3912 (19)	0.4721 (5)	0.084 (6)
Si1	0.0000	0.6887 (15)	0.3702 (4)	0.046 (5)
C1	0.0000	0.694 (4)	0.0740 (14)	0.045 (2)*
H11	0.0000	0.8375	0.0247	0.054*
H12	−0.1022	0.6234	0.0207	0.054*	0.50
H12A	0.1022	0.6234	0.0207	0.054*	0.50
C2	0.2020 (11)	0.815 (3)	0.4833 (16)	0.068 (14)
H21	0.2983	0.7629	0.4031	0.081*
H22	0.2149	0.7785	0.6316	0.081*
H23	0.1974	0.9622	0.4700	0.081*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0595 (18)	0.125 (18)	0.0667 (15)	0.000	0.000	0.000 (7)
Si1	0.0391 (13)	0.064 (15)	0.0360 (11)	0.000	0.000	0.011 (5)
C2	0.064 (4)	0.09 (4)	0.045 (3)	−0.013 (9)	−0.012 (3)	−0.002 (11)

Geometric parameters (Å, º)

Cl1—Si1	1.988 (14)	Si1—C2	1.878 (12)
Si1—C1	1.825 (9)	Si1—C2^i	1.878 (12)
C1—Si1—C2	111.3 (5)	C1—Si1—Cl1	109.4 (10)
C1—Si1—C2^i	111.3 (5)	C2—Si1—Cl1	106.7 (7)
C2—Si1—C2^i	111.2 (12)	C2^i—Si1—Cl1	106.7 (7)

Symmetry code: (i) −x, y, z.