Styx numbers

Although the styx numbers quantify the various stmctural features present in a compound, molecules that are closely related may have very different styx numbers. For example, and B H q have similar stmctures, but styx numbers of 0260 and 4220, respectively. A simplified styx system has been... 

Fig. 1-1. The original neutral boron hydrides (boranes) isolated by Stock along with their styx numbers.

Fig. 6. The valence structures and styx numbers of BbH9, B4H10, and B6H...

The overall bonding in borane molecules or anions is sometimes represented by a 4-digit code introduced by Lipscomb, the so-called styx number, where... 

Skeletal electron counts (the sum of the styx numbers), first proposed by Wade, Mingos, and Rudolph, have also provided a guide for synthesis, and have given a basis for filled bonding description of polyhedral species and their fragments. Together with the isolobal concept, diverse areas of chemistry have thereby been unified. 

Dikshit, S.K. and Singh, R. (1992) Semi-topological representation of electronic stmcture of complex boron hydrides and ions using Styx numbers. J. Chem. Educ., 69 (4), 274. 

Although the free molecule B2H4 is unknown, the species continues to attract the attention of theoretical chemists. Several suggested possible structures (I to XI) for the uncomplexed species are given in Fig. 2-56 along with their symmetry point groups and styx numbers [2 to 4]. 

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