First-principles study on the lattice dynamics and thermodynamic properties of Cu2GeSe3 Hezhu Shao, Xiaojian Tan, Tianqi Hu, Guo-Qiang Liu, Jun Jiang and Haochuan Jiang EPL, 109 4 (2015) 47004 Published online: 02 March 2015 DOI: 10.1209/0295-5075/109/47004