{'fraction_non_alphanumeric': 0.04007633587786259, 'fraction_numerical': 0.04103053435114504, 'mean_word_length': 5.435582822085889, '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}}
A3Sr2P7O21 (A = Rb, Cs): Two Polyphosphates Based on Different Types of P-O Chains and Ring Structures.

Two polyphosphates containing two types of polymerization of the [PO4] groups, Rb3Sr2P7O21 and Cs3Sr2P7O21, were grown through a spontaneous nucleation method. Single-crystal X-ray diffraction data were collected in order to determine their structures. Interestingly, Rb3Sr2P7O21 is the first example of two kinds of [PO3]∞ linear chains coexisting in one phosphate structure. However, in the structure of Cs3Sr2P7O21, the isolated [P4O12] ring and the 1D [PO3]∞ chain can be observed, which is also rare in phosphates. After careful structural analysis, the alkali-metal cations have an effect on the polymerization of the [PO4] groups and make Rb3Sr2P7O21 and Cs3Sr2P7O21 crystallize in different space groups. What is more, IR spectra, UV-vis-NIR diffuse reflectance spectroscopy data, and first-principles theoretical calculations were adopted to determine the optical properties and the structure-properties relationship of the compounds.