摘要
In the present work, we find that both diffusion activation energy Ea(D) and Ea(S^ex) increase linearly with pressure and have the same slope (0.022±0.001 eV/GPa) for liquid Al. The temperature and pressure dependence of excess entropy is well fitted by the expression -S^ex (T, P)/kB = a(P)+ b(P)T + c(P) exp(Ef/kBT), which together with the small ratio of Ef/kB T leads to the relationship of excess entropy to temperature and pressure, i.e. Sex ~ -cEf/T, where c is about 12 and Ef (= △E - P△V) is the favourable energy. Therefore, there exists a simple relation between Ea(S^ex) and Ef, i.e. Ea(S^ex) ≈ cEf.
In the present work, we find that both diffusion activation energy Ea(D) and Ea(S^ex) increase linearly with pressure and have the same slope (0.022±0.001 eV/GPa) for liquid Al. The temperature and pressure dependence of excess entropy is well fitted by the expression -S^ex (T, P)/kB = a(P)+ b(P)T + c(P) exp(Ef/kBT), which together with the small ratio of Ef/kB T leads to the relationship of excess entropy to temperature and pressure, i.e. Sex ~ -cEf/T, where c is about 12 and Ef (= △E - P△V) is the favourable energy. Therefore, there exists a simple relation between Ea(S^ex) and Ef, i.e. Ea(S^ex) ≈ cEf.
基金
Project supported by the National Natural Science Foundation of China(Grant Nos.10674135,10874182 and 50803066)
the Foundation of the Education Committee of Anhui Province,China(Grant Nos.KJ2010A031 and KJ2010A012)
the Funds from the Centre of Computational Science,Hefei Institutes of Physical Sciences