Crystal structure studies, coordination compounds

As far as I know, crystal structure studies have not been published on this kind of compound. But I think they would be revealing and by analogy perhaps tell us something about the melt situation. If one can determine—and I am sure it is possible by x-ray analysis of these compounds—what the nitrate coordination is around the metal ion, one might be able to infer something about the melt situation. 

Zhang et al. [41] studied the crystal structure of the compound Ca3La3(B03)5 and, by means of infrared spectra, they confirmed that the boron atoms have three-fold coordination. DTA revealed that reversible decomposition takes place at 1165 C and that it melts completely above 1300 °C. 

The author s thanks go to Prof. Tadeusz Gtowiak, who resolved the crystal structure of all compounds presented in the paper, and to Izabela Czelusniak, who studied the catalytic activity of seven-coordinate compounds. Financial support from the Polish State Committee for Scientific Research (grant no. 3T09A 059 17 and... 

All (pentafluorophenyl)germyl- and -stannylmercurates of lanthanoids are isolated as noncrystalline solids therefore they could not be studied with X-ray diffraction analysis. In contrast, the nonfluorinated analog [(Ph3Ge)3Hg]2Yb(THF)2(DME)2, obtained from the interaction of (Ph3Ge)2Hg with naphthaleneytterbium, precipitates from a THF/DME solution as yellow crystals [26]. The X-ray analysis has shown that the crystal structure of this compound consists of the isolated cations [Yb(DME)2 (THF)2] with an octahedral coordination at the Yb atom and the anions [(QF5)3-Ge]3Hg" with a planar trigonal coordination at the Hg atom. These data confirm the above cited supposition on the structure of similar complexes. 

In contras t with dially lamines and their sulfonyl derivatives, IV-acy Idially lamines react with tellurium tetrahalides to give zwitterionic oxazolines 29 containing five-coordinated tellurium (85T1607). Molecular and crystal structures of one of this type of compound (29, R = Me, X = Cl) were studied by X-rays (85T1607). 

Konig and others published in the 1970s an impressive series of studies on six-coordinate iron(II)-bis-phenanthroline complexes [160-164] for which they inferred 5=1 from thorough magnetic susceptibility and applied-field Mossbauer measurements. Criteria for the stabilization of the triplet ground state for six-coordinate compounds with tetragonal ( >4 ) and trigonal ( >3 ) symmetry were obtained from LFT analyses [163], The molecular structures, however, were not known because the materials could not be crystallized. 

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