Structural transitions in Mo8O23

Abstract
By means of neutron and X-ray four-circle diffractions, evidence for two structural transitions in Mo8O23 has been found. The incommensurate phase appears at a value of Tcl higher than room temperature and the incommensurate-commensurate transition takes place at Tc2 approximately=285K. The idea that the transitions are associated with the charge-density wave formation can explain the temperature dependences of the magnetic susceptibility and the electrical resistivity consistently. The characteristic features of the condensed mode in the commensurate phase are discussed.