Dicarba-closo-dodecaborane(12) derivatives of phosphonium salts: easy formation of nido-carborane phosphonium zwitterions

The first examples of arylphosphonium salts containing a dicarba-closo-dodecaborane(12) (closo-carborane) are reported; in contrast to the 1,12-carborane derivative, the 1,2- and 1,7-isomers undergo a facile deboronation reaction in polar solvents to afford the corresponding nido-carborane phosphonium zwitterions

The Connection between the Properties of Elements and Compounds; Mineralogical-Crystallochemical Classification of Elements

The described mineralogical-crystallochemical classification bears some similar features with geochemical classification of elements. This similarity emphasizes a greater importance in conforming the vast practical data on petrology. The present classification also bears some resemblance to the technical classification of elements by Berg (1929). The similarity seems logical since the mineralogical. crystallochemical classification of elements unites them on the basis of crystallochemical similarity, determining the type of chemical bonds of the formed compounds, the possibility of crystalline substances. In their turn they determine the common mineral genesis in one mineralogical-crystallochemical group of elements, their co-existence in ores and chemical raw materials and the possiblity of formation of alloys