C-D bond length

The C—H and C—D bond lengths are the same, 1.085 when one takes into account the anharmonicity of the vibrations. Thus it would seem that steric effects are not essential for the helical arrangement. 

The methyl groups are accordingly above and below the general plane of the molecule, leading to the existence of enantiomers for such molecules. The rates of racemi-zation of A and B have been measured, and, because of the shorter C-D bond lengths, the two methyls interfere less seriously with one another in B than in A, and the race-mization rate is, therefore, significantly faster for B, as is well reproduced by molecular mechanics. ... 

The sydnones may be represented by structures (123a-d), of which the zwitterionic structure (123a) most clearly implies an aromatic sextet. The diamagnetic susceptibility exaltation for Af-phenylsydnone of ll.Ox 10 cm moP is comparable with the corresponding value for pyrrole (10.2x10 ). 3-p-Bromophenylsydnone (123 R = H, R = p-bromophenyl) is essentially planar however, the O—N bond and 0(1)—C(5) bond lengths are not very different from normal single bond distances. 

More definite evidence comes from an MO study of the S—O stretching in dimethyl sulphoxide9, where three basis sets were employed a STO-3G one (I), a 4-31G one (double-zeta, II) and a 3G + d one (III). Table 6 reports the main results the small effect of the double-zeta, and the dramatic effect of the 3d functions, are clearly visible. Notice also how the C—S bond length and the bond angles are by far less sensitive to basis set changes. 

P212121 Z = 4 D = 2.01 R = 0.04 for 1,611 intensities. The compound is a minor product in the synthesis of methyl tyveloside. The pyranose conformation is a distorted 4, with Q = 66 pm 6= 162° (p=H8a. The (methylthio)carbonyl side-chain is extended. The C-S bond-lengths are 174.8, 179.1 pm. The C-I bond-length is 215.2 pm. The absolute configuration was confirmed by using the anomalous-scattering factors of the iodine atoms. 

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