First principles calculation of thermal expansion coefficient - Part 1. Cubic metals

Based on the Debye-Gruneisen approximation, we conducted coefficient of thermal expansion (CTE,alpha) calculations for nine pure cubic metals (Pd, Cu, Ag, Rh, V, Nb, Rb, K and Al) using density functional theory. Employing Pd, Cu, and Ag as benchmark, we compared the numerical performance of CTE for four density functional theory (DFT) methods, namely LDA, LSDA, GGA and GGS. For these three metals, we found that the gradient-corrected methods (GGA and GGS) yields much larger CTE compared to the local-density methods (LDA and LSDA). By comparing with experimental CTE, we found that the GGA approach yields the best estimate for this property when a 'cutoff radius' of 10% is used. For the nine pure cubic metals investigated here, the mean-absolute-deviation of the GGA CTE is found to be less than 3% from the experimental value (except for Al), which represents a major improvement over previous LDA-based calculation. To further explore the applicability of the developed CTE calculation protocol, we extend the GGA calculation to eight compounds (AlNi, AgMg, AuCd, GaNi, Pd3Sn, AlNi3, AuCu3 and Al3U) with cubic structures. Good agreement with experiment was obtained, indicating the feasibility of applying the same technique on ordered alloys. (C) 2002 Elsevier Science B.V. All rights reserved.