Pressure coefficient K0′ of bulk modulus for cubic elements



The Grüneisen relation Γ = αpKTV/Cν has been integrated with respect to T at constant volume. This leads to a potential E(V) with the two exponents Γ = m/3 and δ = n/3. The Grüneisen constant Γ is the exponent of the repulsive term. The exponent δ of the attractive term may be determined from heat capacity, thermal expansion and cohesive energy, δ = Cppc.

The pressure coefficient of the bulk modulus of an m-n potential E(V) is given by K0′ = m/3 + n/3 + 2. According to the calculations above we obtain K0′ from thermophysical data by K0′ = Γ + δ + 2 = αpKTV/Cν + Cppc + 2, with K0′ = 4-5 for alkali metals, K0′ = 5.2-6.2 for transition metals and K0′ = 7-8 for solid rare gas crystals. This is in good agreement with high pressure data.