Modification of the statistical moment method for the high-pressure melting curve by the inclusion of thermal vacancies

Theoretical insights into non-Arrhenius behaviors of thermal vacancies in anharmonic crystals

“…In prior SMM works, [23][24][25] the cohesive energy of FCC metals was predominantly modeled by the Lennard-Jones (LJ) pairwise potential as 33…”

“…Another viable approach for determining the equilibrium vacancy concentration is the statistical moment method (SMM). [23][24][25] This quantum model is well suited to characterize vibrational excitations in pure metals, 26 solid solutions, 27 and ionic compounds. 28 Interestingly, its mathematical aspects are straightforward and transparent.…”

“…For instance, the underlying correlation among melting transition, elastic deformation, and vacancy formation has been elucidated in recent SMM works. 24,25 Nevertheless, non-Arrhenius behaviors of vacancies have not been fully understood. As mentioned above, [19][20][21][22] this limitation is most likely a consequence of combining the SMM with the QHA.…”

“…As mentioned above, [19][20][21][22] this limitation is most likely a consequence of combining the SMM with the QHA. [23][24][25] Herein, we develop the SMM to achieve a more reliable picture of the vacancy evolution. Theoretical calculations are performed for representative transition metals with the facecentered cubic (FCC) structure, including Ag, Cu, and Ni.…”

Study on the Melting Temperature, the Jumps of Volume, Enthalpy and Entropy at Melting Point, and the Debye Temperature for the BCC Defective and Perfect Interstitial Alloy WSi under Pressure

“…At constant P and constant interstitial atom concentration, the melting temperature T R m of a defective crystal is the function of the equilibrium vacancy concentration n v . Approximately, the following relations can be applied [2,34]:…”