data_global _chemical_name_mineral 'Gotzenite' loop_ _publ_author_name 'Bellezza M' 'Merlino S' 'Perchiazzi N' _journal_name_full 'European Journal of Mineralogy' _journal_volume 16 _journal_year 2004 _journal_page_first 957 _journal_page_last 969 _publ_section_title ; Chemical and structural study of the Zr,Ti-disilicates in the venanzite from Pian di Celle, Umbria, Italy ; _database_code_amcsd 0007084 _chemical_compound_source 'Pian di Celle, Umbria, Italy' _chemical_formula_sum 'Ca5.66 Zr.28 Na1.06 Ti.98 Si4 O14 F4' _cell_length_a 9.636 _cell_length_b 7.341 _cell_length_c 5.737 _cell_angle_alpha 89.94 _cell_angle_beta 100.74 _cell_angle_gamma 101.06 _cell_volume 391.055 _exptl_crystal_density_diffrn 3.125 _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 _atom_site_occupancy _atom_site_U_iso_or_equiv Ca1 0.63220 0.90960 0.22180 0.86000 0.01300 Zr1 0.63220 0.90960 0.22180 0.14000 0.01300 Ca2 0.63450 0.40780 0.21940 1.00000 0.01100 Ca3 0.99350 0.24210 0.49600 0.68000 0.01800 Na3 0.99350 0.24210 0.49600 0.32000 0.01800 Ca4 0.00000 0.50000 0.00000 0.58000 0.02500 Na4 0.00000 0.50000 0.00000 0.42000 0.02500 Ti5 0.00000 0.00000 0.00000 0.98000 0.01800 Si1 0.71790 0.65290 0.74780 1.00000 0.01200 Si2 0.72290 0.21320 0.75100 1.00000 0.01600 O1 0.75920 0.44240 0.78990 1.00000 0.02400 O2 0.61470 0.66890 0.93390 1.00000 0.01700 O3 0.61810 0.14070 0.93140 1.00000 0.01600 O4 0.64670 0.66480 0.47640 1.00000 0.02100 O5 0.67060 0.16640 0.47550 1.00000 0.02700 O6 0.87910 0.78060 0.81840 1.00000 0.02200 O7 0.88480 0.17220 0.83070 1.00000 0.02300 F1 0.88880 0.47570 0.30590 1.00000 0.01900 F2 0.88560 0.96880 0.26350 1.00000 0.02800