Ra-X bonds

The operation of the cis effect of the porphyrin may be explained according to Case D (Fig. 1) the more basic the porphinato ligand, the more electron density it induces at the metal ion, and the more will the d -electrons at the metal tend to flow away to the 7r-acceptor ligand X, reinforcing the M—X bond (90). An alternative ra-... 

Next, we introduce the vectors a and fB directed toward the hydrogen atoms in the same way as the corresponding covalent bonds. The absolute values of these vectors are equal to the covalent-bond lengths. The linear velocities, referring to rotations, are equal to rA x Q and fB x Q . 

A large number of polymeric substances, (RAs) or (ArAs), are also known (113). They are usually prepared by the reduction of arsonic acids with hypophosphorous acid (100,114) or sodium dithionite (115). Most of these polymers have not been well characterized. An insoluble, purple material, poly(methylarsinidene) [26403-94-1], (CH As), prepared by the interaction of methylarsine and a dihalomethylarsine, however, has been shown by an x-ray investigation to have a ladderlike polymeric stmcture in which the inter-mng distances correspond to one-electron bonds (116) ... 

Mixed labeling involving both x and a orbitals occurs in certain molecules the 5BU molecular orbitals of ra is-2-butene (III.78) and transoid 1,3-butadiene (III.65) are labeled ch3> ( cc) and 7rcn2> ( cc) because one lobe of the x orbital overlaps well with the adjacent CC bond-orbital to form a delocalized combination. In cisoid acrolein, orbitals 9A and 10A are labeled TCH2y nodal surfaces of the two localized orbitals coincide and allow for a delocalized combination (III.G8). 

Figure 3.95 Bond lengths in compounds (ra i-Pt(Pcy3)2X2 (X = H, halogen).

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