{'fraction_non_alphanumeric': 0.04671532846715328, 'fraction_numerical': 0.03795620437956204, 'mean_word_length': 5.533333333333333, '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}}
Evidence for a subtle structural symmetry breaking in EuB6

This work presents a systematic Raman scattering study and first-principles calculations for the EuB6 system. Evidence for the presence of an incipient (∼1 × 10−4 Å) tetragonal symmetry break of its crystalline structure was found. Forbidden Raman modes at ωfRm(1)∼1170 cm−1, ωfRm(2)∼1400 cm−1, and ωfRm(3)∼1500 cm−1 were observed. The tetragonal symmetry of ωfRm(2) and ωfRm(3) together with spin-polarized first-principles simulations of the structural and magnetic properties fully support such a break of symmetry. Our data and calculations explain the occurrence of ferromagnetism in Eu hexaborides, previously reported.