Arsenic complexes structures

Inorganic arsenic complexes based on oxygen ligands is scarce. Simple esters of arsenic acid, As(0)(0R)3 (R = Me, Ft, n-Pr, n-Bu, CeHn) have tetragonal structures. Reaction of the diol ligand 2,4-dimethyl-2,4-pentanediol with AsCfr affords an arsenic chloride complex in which the As atom is part of a six-membered ring (37). ... 

Homoleptic trisquelate arsenic complexes have been only structurally characterized with ligands (41) and (42). The complexes show mainly a distorted octahedral geometry, that is, [As(S2COMe)3] (44), or antiprismatic, that is, [As S2CN(CH2CH20H) 3] (45) (Figure 13). These... 

In solution these substances scatter light, they exhibit high viscosity and low diffusion rates, and they enter into complex structural relations with the solvent. In some of their physical properties the solutions, although they are true solutions by many criteria, simulate the sols and gels of the more truly heterogeneous systems. Owing their stability, however, to the interactions between their own molecules and the solvent, they are less subject to coagulation and precipitation. In so far as they form solutions they are called lyophilic, in contradistinction to the easily precipitable sols of inherently insoluble substances such as metals or arsenic sulphide in water, which are called lyophobic. 

The reflection maxima found in the range E > Eg represented direct band-band transitions at high-symmetry points in the Brillouin zone. The complex structure of the reflection spectra of arsenic chalcogenide crystals was evidence of the complex energy band structure of these compounds. 

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