data_global _chemical_name_mineral 'Merrillite' loop_ _publ_author_name 'Hughes J M' 'Jolliff B L' 'Rakovan J' _journal_name_full 'American Mineralogist' _journal_volume 93 _journal_year 2008 _journal_page_first 1300 _journal_page_last 1305 _publ_section_title ; The crystal chemistry of whitlockite and merrillite and the dehydrogenation of whitlockite to merrillite Note: Formed through dehydrogenation of synthetic whitlockite by heating at 1050 degrees C for 24 hours ; _database_code_amcsd 0004626 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'Ca9.443 (Mg.935 Fe.065) P6.964 O28' _cell_length_a 10.3499 _cell_length_b 10.3499 _cell_length_c 37.115 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 120 _cell_volume 3443.122 _exptl_crystal_density_diffrn 3.092 _symmetry_space_group_name_H-M 'R 3 c' loop_ _space_group_symop_operation_xyz 'x,y,z' '2/3+x,1/3+y,1/3+z' '1/3+x,2/3+y,2/3+z' 'x,x-y,1/2+z' '2/3+x,1/3+x-y,5/6+z' '1/3+x,2/3+x-y,1/6+z' '-y,-x,1/2+z' '2/3-y,1/3-x,5/6+z' '1/3-y,2/3-x,1/6+z' '-x+y,y,1/2+z' '2/3-x+y,1/3+y,5/6+z' '1/3-x+y,2/3+y,1/6+z' '-y,x-y,z' '2/3-y,1/3+x-y,1/3+z' '1/3-y,2/3+x-y,2/3+z' '-x+y,-x,z' '2/3-x+y,1/3-x,1/3+z' '1/3-x+y,2/3-x,2/3+z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy _atom_site_U_iso_or_equiv CaIIB1 0.27347 0.14232 0.56805 1.00000 0.00999 CaIIB2 0.38364 0.17687 0.76923 1.00000 0.01083 CaIB 0.27226 0.14701 0.67506 1.00000 0.01981 CaIIA* 0.00000 0.00000 0.81260 0.44300 0.01470 Mg 0.00000 0.00000 0.00000 0.93500 0.00860 Fe 0.00000 0.00000 0.00000 0.06500 0.00860 PB1 0.31343 0.13900 0.86563 1.00000 0.00944 PB2 0.34384 0.15160 0.96931 1.00000 0.00837 OIB1 0.26151 0.08320 0.82711 1.00000 0.02100 OIIB1 0.24269 0.22849 0.87966 1.00000 0.01820 OIIB3 0.27624 -0.00043 0.88827 1.00000 0.01140 OIIB5 0.48536 0.24023 0.86822 1.00000 0.01480 OIIB2 0.39666 0.04391 0.95679 1.00000 0.01400 OIIB4 0.41985 0.30068 0.94937 1.00000 0.01630 OIIB6 0.17435 0.07693 0.96245 1.00000 0.01120 OIB2 0.37816 0.18167 0.00954 1.00000 0.01300 PA* 0.00000 0.00000 0.73451 0.96400 0.00920 OIA* 0.00000 0.00000 0.69336 1.00000 0.01690 OIIA* -0.00408 0.13809 0.74822 1.00000 0.02240