Kinetics of the decomposition of tetraborane(10)

Abstract

The decomposition of tetraborane(lO) has been studied at 40,50, and 60°and at pressures of 37,73, and 110 Torr at each of these temperatures. The course of the reaction was followed by the periodic analysis of the mixture for tetraborane(lO), diborane, pentaborane(9), and pentaborane(ll). The reaction is 3/2 order in tetraborane(10) at each temperature and pressure except for the 60°runs at the two lower pressures. In these cases the decomposition appears to be approaching first-order behavior.xcellent bibliographies of the thermal decomposition of various boron hydrides may be found in several books.1-5 The studies dealing primarily with the decompositions of tetraborane(lO) are those of

Preparation of aluminoborane analogs of the lower boron hydrides

“…Although this structure is predicted by electron-counting rules, this is the first time it has been observed for an eight-vertex, In + 4 skeletal electron system. Crystal data for II: space group P2,/c; Z = 4, a = 8.838 (4) Á, b = 22.019 (19) A, c = 7.910 (4) A, ß = 114.96 (1)°; V = 1395 (3) A3 45. The structure was refined by full-matrix least squares to a final R of 0.051 and of 0.049 for the 1233 reflections which had F02 > 3a(F02).…”

Kinetics of Boron Hydride Interconversion Reactions

“…This conclusion, which is entirely consistent with Riley Schaeffer's earlier views on this system, is however at odds with another more recent study on the thermolysis of 84410 which has been interpreted in terms of a 3 /2-order process predominant below 60 °C and involving reaction (5b) as the initi.,ting step in a speculative chain mechanism (ref. 23). We therefore undertook a detailed reexamination of the thermolysis of B4410 in the pressure range 0.9-39 mmHg and at temperatures in the range 40-78 'C (ref.…”