Introduction

Short information on the structures of alkali, alkaline earth, rare earth and transition metal oxides and uranium oxides in the crystalline state, as well as Cs2O, SrO, MoO3 and RuO4 molecules in the gaseous state is presented. Data on the main types of crystalline structures of metal oxides: molecular, chain, layer and skeleton are generalized. Structure characteristic properties of oxides, which are connected with their chemical composition, with bond ionic character, with their sizes and valent states of ions