Abstract:
CONTENTS I. Introduction 237 II. Qualitative quantum-mechanical ideas about the formation of electron-deficient bonds 231 III. What is understood by the expressions "energetically favourable orbital" and "utilisation of vacant orbitals" 233 IV. NMR spectra of the boron hydrides 233 V. NMR of organoaluminium compounds 236 VI. NMR of organolithium compounds 237