data_global _chemical_name_mineral 'Lopezite' loop_ _publ_author_name 'Weakley T J R' 'Ylvisaker E R' 'Yager R J' 'Stephens J E' 'Wiegel R D' 'Mengis M' 'Wu P' 'Photinos P' 'Abrahams S C' _journal_name_full 'Acta Crystallographica, Section B' _journal_volume 60 _journal_year 2004 _journal_page_first 705 _journal_page_last 715 _publ_section_title ; Phase transitions in K2Cr3O7 and structural redetermination of phase II Sample: Crystal 2 ; _database_code_amcsd 0009932 _chemical_compound_source 'Synthetic' _chemical_formula_sum 'Cr2 K2 O7' _cell_length_a 7.3837 _cell_length_b 7.4622 _cell_length_c 13.3949 _cell_angle_alpha 96.204 _cell_angle_beta 98.046 _cell_angle_gamma 90.943 _cell_volume 726.122 _exptl_crystal_density_diffrn 2.691 _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 Cr1 0.59177 0.76886 0.60724 Cr2 0.79290 0.80680 0.41370 Cr3 0.81703 0.42577 0.11362 Cr4 0.81338 0.15247 -0.08318 K1 0.10346 0.66920 0.64034 K2 0.25016 0.76715 0.34962 K3 0.66245 -0.08530 0.15847 K4 0.69492 0.65228 -0.13585 O1 0.71960 0.61250 0.64900 O2 0.55470 0.91000 0.70170 O3 0.40240 0.68520 0.54510 O4 0.70760 0.89280 0.52682 O5 0.95910 0.67530 0.44298 O6 0.86880 0.97160 0.36080 O7 0.63440 0.69510 0.33650 O8 0.68900 0.29290 0.16380 O9 0.97560 0.51800 0.20002 O10 0.69490 0.57550 0.06120 O11 0.92930 0.29590 0.02274 O12 0.69190 -0.00030 -0.04335 O13 0.96040 0.06120 -0.14860 O14 0.67740 0.27360 -0.15180 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 Cr1 0.01860 0.02080 0.01890 0.00250 0.00380 0.00250 Cr2 0.01790 0.02060 0.01880 0.00210 0.00390 0.00480 Cr3 0.01870 0.01840 0.01880 -0.00130 0.00030 0.00190 Cr4 0.01670 0.01830 0.02000 0.00030 0.00300 0.00100 K1 0.03710 0.03110 0.02430 -0.00730 0.00210 0.00550 K2 0.03220 0.02680 0.02910 -0.00300 0.00990 0.00200 K3 0.02340 0.02440 0.02590 -0.00030 0.00360 0.00080 K4 0.03740 0.02960 0.02780 0.01030 0.00390 0.00220 O1 0.03200 0.03090 0.04000 0.00970 -0.00030 0.01000 O2 0.04200 0.03460 0.03040 0.00370 0.01520 -0.00260 O3 0.02740 0.04500 0.03340 -0.00460 -0.00220 0.00640 O4 0.03680 0.02480 0.03200 0.00160 0.01650 0.00280 O5 0.02760 0.03160 0.02850 0.01150 0.00340 0.00640 O6 0.04100 0.02730 0.03180 -0.00260 0.00970 0.00980 O7 0.02870 0.04300 0.03310 -0.00420 -0.00200 0.00070 O8 0.02980 0.02910 0.03200 -0.00640 0.00810 0.00360 O9 0.03000 0.03580 0.02210 -0.01020 0.00000 -0.00120 O10 0.04160 0.02910 0.03130 0.01300 0.00240 0.00480 O11 0.01820 0.02700 0.02600 -0.00100 -0.00020 -0.00140 O12 0.03600 0.02450 0.02760 -0.00720 0.00470 0.00360 O13 0.02910 0.04110 0.03900 0.00700 0.01300 -0.00640 O14 0.02630 0.02500 0.03000 0.00200 -0.00170 0.00470