PDF Publication Title:
Text from PDF Page: 040
30 Ralf Steudel · Bodo Eckert Table 9 Molecular structure parameters of crystalline S10 (at 163 K) [35, 97] Point symmetry Av. bond length (pm) Range Av. bond angle (pm) Range Torsion ngle ()a Range a Absolute values 222–D2 205.6 203.3–207.8 106.2 103.4–110.2 95.7 75.4–123.7 Fig. 9 Geometry of the S10 molecule in the crystal (the atoms Si and Si2 are related by the molecular symmetry D2) [97] 116.6 the D2 structure has a mean absolute value of 95.7 which is much closer to the ideal value of about 90. The space group of crystalline S10 is monoclinic C2/c–C2h6 (no. 15) with an unusually small angle of 37 [35, 97]. Four molecules in the unit cell oc- cupy sites of C2 symmetry. The lattice constants are a=1253.3(9) pm, b=1027.5(9) pm, c=1277.6(9) pm at 163 K. The shortest intermolecular distances are 323.1, 324.0, and 329.1 pm, much less than in crystalline S6; however, the S10 molecules are less compact. Therefore, the density of S10 is lower than that of S6 (Table 22). 2.2.1.6 The Compound S6·S10 When S10 was prepared from S6 according to several slightly different proce- dures (see above) the formation of a new sulfur allotrope was observed sev- eral times. This allotrope forms intense orange-yellow, opaque, hexagonal plate-like crystals [34, 35]. An X-ray study on single crystals of this allotrope proved the assumption of a molecular addition compound S6·S10 as had been suggested before by evaluation of the Raman spectrum [34, 35]. The space group of S6·S10 crystals is I2/a which is an alternative setting of C2/n(=C2h3, no. 12) of the monoclinic crystal system. The structure consists of alternating layers of S6 and S10 molecules, respectively, with four mole-PDF Image | Topics in Current Chemistry
PDF Search Title:
Topics in Current ChemistryOriginal File Name Searched:
Elemental-Sulfur-und-Sulfur-Rich-Compounds-I.pdfDIY PDF Search: Google It | Yahoo | Bing
Sulfur Deposition on Carbon Nanofibers using Supercritical CO2 Sulfur Deposition on Carbon Nanofibers using Supercritical CO2. Gamma sulfur also known as mother of pearl sulfur and nacreous sulfur... More Info
CO2 Organic Rankine Cycle Experimenter Platform The supercritical CO2 phase change system is both a heat pump and organic rankine cycle which can be used for those purposes and as a supercritical extractor for advanced subcritical and supercritical extraction technology. Uses include producing nanoparticles, precious metal CO2 extraction, lithium battery recycling, and other applications... More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)