Unstable intermediates. Part CLXII. Electron spin resonance studies of ClOCl+, FClO+, and Cl4+

Abstract

Fluid and solid-state e.s.r. spectra for the title radicals formed from molecular chlorine and antimony pentachloride are described and approximate orbital populations derived therefrom. The novel radical Cl₄⁺, only detected at 77 K, is throught to be planar, being formed from Cl₂+ and Cl₂ by a weak π*–π* interaction. Structural considerations suggest the assignment: g_x= 2.00 g_y= 2.031, g_z= 2.125 and A_x(³⁵Cl)= 48G, A_y= O ± 4 G, and A_z= 0 ± 4 G, where x is the principal direction of the combined π* orbital, z is the direction of the original σ bonds, and y is normal to the plane.