S distance

The fdr studies reveal that the alkyl chains in SAMs of thiolates on Au(lll) usually are tilted 26-28° from the surface normal, and display 52-55° rotation about the molecular axis. This tilt is a result of the chains reestabUshing VDW contact in an assembly with - 0.5 nm S—S distance, larger than the distance of - 0.46 nm, usually quoted for perpendicular alkyl chains in a close-packed layer. On the other hand, thiolate monolayers on Ag(lll) are more densely packed owing to the shorter S—S distance. There were a number of different reports on chain tilt in SAMs on Ag(lll), probably owing to different amounts of oxide, formed on the clean metallic surface (229,230,296,297). In carefully prepared SAMs of alkanethiolates on a clean Ag(lll) surface, the alkyl chains are practically perpendicular to the surface. 

The N—CO distance of 1.38 A in (58) is rather greater than that of a normal amide (ca. 1.32 A) this has been attributed to ring strain and to inhibition of normal amide resonance by interaction with the N-aryl substituent. This inhibition of resonance is more pronounced in the N-tosyl-4-thioxoazetidin-2-one (59), which exhibits very short C=0 and C=S distances as well as the unusually long C—N bonds (80TL4247). NMR investigations... 

If the centrifuge operates at 4000 rpm and the particle s distance from the axis of rotation is 0.25 m, the settling velocity is only 0.01 m/sec, which corresponds to ... 

The worker and the tool should be outside the exhaust system s distance of influence and the source should be inside this distance, as is shown principally in Fig. 10.8. 

S Distance between the axis of the initial section of the linear jet air curtain... 

The S S distance in the dimer of the thiatrazinyl radical 4.16 (E = S) is 2.67 similar to the values observed for the intramolecular S S interactions in 4.12 (R = NMc2) and 4.1. Indeed this dimerization involves a interaction analogous to those depicted in Eigure 4.8... 

The 1,5-isomers 13.3 (E = S) are colourless, air-stable solids. They are prepared by the cyclocondensation reaction of R2PN2(SiMe3)3 with sulfur dichloride or thionyl chloride. A similar cyclocondensation process, using a mixture of SeCU and Sc2Cl2 as a source of selenium, produces a mixture of the isomers 13.2 and 13.3 (E = Se, R = Ph). The structures of 13.3 (E = S, R = alkyl, aryl) are folded eight-membered rings with a cross-ring S S distance of ca. 2.50 This structural... 

The regular octahedral structure of SFg and the related structure of S2F]q (Fig. 15.20) call for little comment except to note the staggered (D4d) arrangement of the two sets of Feq in S2F10 and the unusually long S-S distance, both features presumably reflecting interatomic repulsion between the F atoms. SFg is also of... 

Figure 15.23 Structure of the [S2l4] cation of C2 symmetry, showing the very short S S distance and the rather short I-I distances note also the S-I distances which are even longer than in the weak charge transfer complex [(H2N2CS)2l]+ (262.9 pm). The nonbonding I I distance is 426.7 pm.

All have pyramidal molecules (Cj point group for OSX2), and OSFCl is chiral though stereochemically labile. Dimensions are in Table 15.14 the short O-S distance is notable. The unstable compound OSI2 was mentioned on p. 692. 

S-O 164.5 pm, S-O, 144 pm) they are made by thermal dehydration of MHSO4. Likewise the trisulfate ion SsOio " is known and also the penta.sulfate ion, SsO, whose structure indicates an alternation of S-O interatomic distances and very long O-S distances to the almost planar terminal SO3 groups ... 

The dithionite ion has a remarkable eclipsed stmcture of approximate C2v symmetry (Fig. 15.32b). The extraordinarily long S-S distance (239 pm) and the almost parallel SO2 planes (dihedral angle 30°) are other unusual features. Electron-spin-resonance studies have shown the presence of the S02 radical ion in solution ( 300ppm), suggesting the establishment of a monomer-dimer equilibrium 8204 ... 

Figure 29.3 Some polymeric complexes (a) Interpenetrating adamantine frameworks in M(CN)2, M = Zn, Cd. (Only M shown straight lines are CN forming linear MCNM rods .) (b) [Zn(acac)2]3, (c) [Cd S=C(NHCH2)2 2(SCN)2], and (d) [M(S2CNEt2)2]2, M = Zn, Cd, Hg. (Note that M is 5-coordinate but with one M-S distance appreciably greater than the other four.)...

The structures of the cis- and frans-isomers of Pt(l,4-thioxane)2Cl2 have been determined. The Pt—S distance (2.298 A) is longer in the frans-isomer than in the cis-form (2.273 A) showing the frans-influence of thioxane to be greater than that of chloride [119],... 

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