{'fraction_non_alphanumeric': 0.013856812933025405, 'fraction_numerical': 0.0, 'mean_word_length': 5.382352941176471, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Free energy and entropy of diffusion by ab initio molecular dynamics: Alkali ions in silicon.

We have calculated the free energy of diffusion for lithium, sodium, and potassium ions in crystalline silicon by combining a thermodynamical integration method with ab initio molecular dynamics simulations. The entropy of diffusion is found to be negative, and its magnitude increases with increasing atomic size of the diffusing species