data_global _chemical_name_mineral 'Lopezite' loop_ _publ_author_name 'Brunton G' _journal_name_full 'Materials Research Bulletin' _journal_volume 8 _journal_year 1973 _journal_page_first 271 _journal_page_last 274 _publ_section_title ; Refinement of the structure of K2Cr2O7 ; _database_code_amcsd 0014228 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'K2 Cr2 O7' _cell_length_a 7.4200 _cell_length_b 13.399 _cell_length_c 7.3845 _cell_angle_alpha 98.03 _cell_angle_beta 90.88 _cell_angle_gamma 96.18 _cell_volume 722.403 _exptl_crystal_density_diffrn 2.705 _symmetry_space_group_name_H-M 'P -1' loop_ _space_group_symop_operation_xyz 'x,y,z' '-x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z K1 0.66919 0.14053 0.10380 K2 0.23292 0.15052 0.74983 K3 0.34729 0.63594 0.30460 K4 0.08500 0.34153 0.33748 Cr1 0.19317 0.08615 0.20690 Cr2 0.76885 0.10722 0.59195 Cr3 0.84734 0.58327 0.18665 Cr4 0.57394 0.38661 0.18305 O1 0.32500 0.05700 0.04100 O2 0.02950 0.13950 0.13120 O3 0.10680 0.97320 0.29190 O4 0.30490 0.16300 0.36520 O5 0.38780 0.85080 0.27930 O6 0.09030 0.79810 0.44510 O7 0.31530 0.95470 0.59790 O8 0.70370 0.47740 0.07030 O9 0.48160 0.30000 0.02410 O10 0.70660 0.33620 0.31130 O11 0.42430 0.43950 0.30490 O12 -0.00030 0.54320 0.30790 O13 0.72620 0.65200 0.32290 O14 0.93880 0.64870 0.03980 loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_12 _atom_site_aniso_U_13 _atom_site_aniso_U_23 K1 0.03278 0.02123 0.03816 0.00493 -0.00920 0.00190 K2 0.02919 0.02704 0.03410 0.00197 -0.00396 0.00972 K3 0.03140 0.02590 0.03843 0.00207 0.00819 0.00337 K4 0.02644 0.02440 0.02435 0.00054 -0.00188 0.00332 Cr1 0.02195 0.01700 0.01948 0.00424 0.00044 0.00356 Cr2 0.02278 0.01726 0.01965 0.00202 0.00076 0.00371 Cr3 0.02027 0.01797 0.01802 0.00089 -0.00117 0.00283 Cr4 0.02060 0.01638 0.02043 0.00158 -0.00281 0.00015 O1 0.03222 0.02731 0.02760 0.00640 0.00874 0.00342 O2 0.03140 0.03083 0.04086 0.01182 -0.00328 0.01172 O3 0.02561 0.02819 0.03870 0.00296 -0.00055 0.01611 O4 0.04710 0.03171 0.02841 -0.00099 -0.00956 -0.00342 O5 0.03250 0.03699 0.03301 0.01084 0.01010 0.00195 O6 0.03663 0.02642 0.04303 -0.00443 0.00191 0.01465 O7 0.04600 0.03083 0.02517 0.00542 -0.00655 -0.00244 O8 0.02864 0.02290 0.01921 -0.00296 -0.00218 0.00098 O9 0.03663 0.02026 0.03139 -0.00049 -0.01256 -0.00244 O10 0.02947 0.03083 0.03085 0.00345 -0.00874 0.00879 O11 0.03167 0.02731 0.04276 0.00542 0.01037 0.00146 O12 0.02561 0.02731 0.03518 0.00443 -0.00846 0.00391 O13 0.02837 0.02466 0.02733 0.00443 -0.00082 -0.00195 O14 0.04242 0.03699 0.03112 -0.00936 0.00328 0.01318