Thermal expansion associated with the charge-density wave inK0.3MoO3

Specific heat at CDW transitions in bronzes

“…Furthermore, that fit, when compared to the measured pressure dependence of Tc, predicted a mean-field specific heat step of 0.17R [7], close to the value we measure.…”

“…The fit is shown in Figure 1; the parameters of the critical "cusp" are i=1.85 and h=0.54, reasonably close to the values obtained from the thermalexpansivity (2.6 and 0.6) [7]. The crossover region is a large fraction of T, .…”

“…The effects of fluctuations at the CDW transition on the thermal expansion coefficients [7] of blue bronze have been successfully fit by an expression [8] smoothly crossing over from mean-field far from T , to 3d-XY critical behavior near Tc. Furthermore, that fit, when compared to the measured pressure dependence of Tc, predicted a mean-field specific heat step of 0.17R [7], close to the value we measure.…”

Dimensional Crossover in the Purple BronzeLi0.9Mo6O17

“…Furthermore, the features in Fig. 3 near T M differ markedly from those observed in well-known phonon-induced CDW systems 266405-2 such as K 0:3 MoO 3 [10,11], where sizable jumps in i , , and heat capacity occur. The absence of such characteristic behavior leads us to conclude that the upturn in the electrical resistivity at T M is not the result of a phonon-induced CDW transition.…”

“…Related Mo compounds [10,11] are well-known CDW systems because structural distortions due to Peierls instabilities are observed through diffraction or thermal expansion experiments; herein this is referred to as a phonon-induced CDW. For Li 0:9 Mo 6 O 17 , high-resolution x-ray diffraction reveals no phonon-induced CDW [12] and a difference of opinion exists in interpreting the photoemission data: in one case they are thought to support LL behavior [2], while in the other Li 0:9 Mo 6 O 17 is classified as a 3D metal above T M and a gap is observed below, consistent with CDW behavior [8].…”