Electrical resistivity of the quasi-two dimensional diphosphate tungsten bronzes Kx(P2O4)2(WO$_3)_{2m}$, $m = 8$

Abstract

We report a study of the resistivity as a function of temperature (4 K<T<300 K) of single crystals of the quasi-two dimensional diphosphate tungsten bronzes (DPTBh) Kx(P2O$_4)_2$(WO$_3)_{2m}$ m=8 for 1.30<x<1.55. A change from metallic to non-metallic behavior is observed for x<1.30. The results are discussed in terms of disorder and in relation with available band models.