X-ray diffraction studies and thermal and elastic properties of 2 H -Ta Se 2
1978; American Physical Society; Volume: 18; Issue: 10 Linguagem: Inglês
10.1103/physrevb.18.5820
ISSN1095-3795
AutoresJoseph L. Feldman, C.L. Vold, E. F. Skelton, Siwei Yu, Ian L. Spain,
Tópico(s)Transition Metal Oxide Nanomaterials
ResumoThe pressure dependences of the lattice parameters $a$ and $c$ of $2H$-Ta${\mathrm{Se}}_{2}$ are determined by x-ray diffraction techniques for $p\ensuremath{\le}4.4$ GPa. In addition, linear thermal expansions are also determined by x-ray diffraction techniques for $10\ensuremath{\le}T\ensuremath{\le}300$ K. The initial ($p=o$) linear compressibilities are obtained and combined with known (zero-sound) elastic moduli (based on neutron-diffraction measurements), primarily to determine ${c}_{13}$; resulting values of ${c}_{13}$ are in the range -2-+2 (${10}^{11}$ dyn/${\mathrm{cm}}^{2}$). Gr\"uneisen parameters and properties of the normal-state to incommensurate-charge-density-wave transition are considered on the basis of our results. It is also shown that, as for $2H$-Nb${\mathrm{Se}}_{2}$, the room-temperature elastic moduli yield too small a value for the ${T}^{3}$ contribution to the low-temperature specific heat.
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