Criteria of selecting strain and fitting schemes are proposed for the calculation of higher-order elastic constants more efficiently, robustly and accurately. As demonstrated by the third-order elastic constants (TOECs) of diamond, the proposed method is 3-5 times faster than existing methods, and the range of strain for getting correct TOECs is expanded. In addition, our result provides an evidence for the inaccuracy of some previous experiments caused by higher-order effect, and the difference among experiments and several different theoretical methods is resolved. Finally, we give the recommend TOECs values for diamond.
@article{arxiv.2009.09963,
title = {Selection of strain and fitting schemes for calculating higher-order elastic constants},
author = {Mingqing Liao and Yong Liu and Fei Zhou and Tianyi Han and Danni Yang and Nan Qu and Zhonghong Lai and Zi-Kui Liu and Jingchuan Zhu},
journal= {arXiv preprint arXiv:2009.09963},
year = {2020}
}