{'fraction_non_alphanumeric': 0.03857142857142857, 'fraction_numerical': 0.027142857142857142, 'mean_word_length': 4.043165467625899, '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}}
X-Ray Study of the Phase Transitions in K3D(SO4)2 and K3H(SO4)2

Structural phase transition of K 3 D(SO 4 ) 2 was studied by X-ray scattering experiments, and new reflections were observed below T c =85 K. The space groups are A 2/ a ( Z =4) above T c and P 2 1 / a ( Z =4) below T c . The postulated structure of the low temperature phase has an antipolar character. Temperature dependence of lattice parameters was also investigated, whose anomaly below T c was marginally small. The deviation from the curve calculated by the Debye approximation was utilized to estimate the nature of the order parameter. Similar experiments in K 3 H(SO 4 ) 2 have not shown any evidence of the phase transition.