Some Physical Parameters of Calcium Chalcogenides at High Pressures: Semi-Empirical Approach

Abstract

Based on the experimental equations of state (EOS) of the parameters reported in the literature, in the present work, we reproduced the variation in the unit cell volume up to phase transition pressure for calcium-based chalcogenide CaX (X  S, Se, Te) semiconductor materials. We also studied the high-pressure effect on the crystal density, isothermal bulk modulus, the first order pressure derivative of the isothermal bulk modulus, and the Grüneisen parameter for CaX (X  S, Se, Te) binary compounds. It was found that, as the pressure increases, both the crystal density and the isothermal bulk modulus increase, while the first order pressure derivative of the bulk modulus and the Grüneisen parameter decrease gradually for all materials of interest. Similar behaviors of all these parameters against pressure were observed for several materials in the literature.

Bulk modulus of CaO under high pressure up to 65 GPa

“…Similar behavior for the bulk modulus versus pressure was observed for the two approaches. Similar behavior for the bulk modulus under pressure was observed for calciumbased chalcogenides CaX (X = S, Se, Te) [20], cubic zincblende (B3) aluminum phosphide (AlP) semiconducting compound [24], and cubic zincblende thallium -phosphide (TlP) material [25]. The fit of our data on the bulk modulus as a function of pressure p (where both B and p are expressed in GPa) obeys the 2 nd order polynomial expression: B = 115.37 + 3.84 p -7.25 x 10 -3 p 2 .…”

“…In object to investigate the effect of high pressure on the bulk modulus of CaO material, we used the Vinet's equation of state (EOS) model. For more details on the relationships between pressure p, relative volume (V/V0), equilibrium bulk modulus B and the first-order pressure derivative of the bulk modulus B′0, please see Ref [20]. Using the experimental parameters (V0 = 27.83 Å 3 , B0 = 114.7 GPa, and B′0 = 4.1) reported by Mammon et al [22], the obtained values of the bulk modulus B versus pressure p for CaO compound are reported in table 1 and traced in Fig.…”

“…Using different theoretical, semi-empirical and empirical approaches, several works [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] have successfully studied different physical properties of many materials with different crystallographic structures. Okba and Mezouar [20] have investigated some physical parameters of calcium chalcogenides at high pressures using semi-empirical approach, while Tsuchiya and Kawamura [21] have studied the elastic properties and their pressure dependence of four alkaline earth oxides (MgO, CaO, SrO, and BaO) binary compounds using the ab initio full-potential linear muffin-tin-orbital (FP-LMTO) method. In the present work, we try to investigate the effect of high pressure up to 65 GPa on the bulk modulus of calcium oxide (CaO) material using only the equilibrium experimental data reported by Mammon et al [22].…”

Mechanical and Thermal Behavior of Semiconducting Cadmium Oxide at High-Pressure

“…In the case of hydrostatic compression, the incompressibility of the material could be characterized by the bulk modulus [12][13][14][15]. If we consider the Vinet universal equation of state (EOS) model [11], the isothermal bulk modulus B of the material could be given with the following expression [17][18][19]:…”

“…It helps on the knowledge of the frequency distribution of the phonon spectrum in solids [18]. There are different methods and approaches usually employed to measure or estimate the Grüneisen parameter  of materials [15][16][17][18][19][20]. Under compression, the Grüneisen parameter  may be calculated for example via the Vashchenko-Zubarev formula as follows [16,19,20]:…”