Solid-State Materials with Polar Bonds

Solid-State Materials with Polar Bonds... 

Polar bonds, solid-state materials with. 276-288 Polarizability tensor, 67 Polarization of ions, 129-134... 

In this review, we present a selection of studies from our own laboratory, intended to introduce a solid-state chemist to both the practical and theoretical considerations that need to be taken into account in XPS measurements of solids with substantial covalent character. Metal phosphides, arsenides, and antimonides represent such a category of solids where the bonding retains some polarity that notions of electron counting derived from the Zintl concept still prove helpful in providing a frame of reference for comparing charge distributions. We also describe the applications of XAS to complementary studies of the electronic structure of these materials. 

The general intransigence of the crystalline iminolithium hexamers toward further interaction with Lewis bases is not shown by the amorphous diaryliminolithiums. This may reflect their extensively stacked nature (Section II,A Fig. 10), which, while raising the lithium coordination number to four in all but the outer rings of the polymer, will presumably weaken individual N—Li bonds. These materials dissolve quite readily in several polar solvents, e.g., THF (66), pyridine (66, 78, 85), and HMPA (86). Crystalline complexes can be recovered from these solutions. Two of these, both derivatives of (Ph2C=NLi) , have been characterized structurally in the solid state. The tetrameric cubane (Ph2C=NLipyridine)4 (7) is depicted in Fig. 14 (78, 85). 

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