data_global _chemical_name_mineral 'Megakalsilite' loop_ _publ_author_name 'Khomyakov A P' 'Nechelyustov G N' 'Sokolova E V' 'Bonaccorsi E' 'Merlino S' 'Pasero M' _journal_name_full 'The Canadian Mineralogist' _journal_volume 40 _journal_year 2002 _journal_page_first 961 _journal_page_last 970 _publ_section_title ; Megakalsilite, a new polymorph of KAlSiO4 from the Khibina alkaline massif, Kola Peninsula, Russia: mineral description and crystal structure ; _database_code_amcsd 0005778 _chemical_compound_source 'Khibina alkaline massif, Kola Peninsula, Russia' _chemical_formula_sum 'Si Al K O4' _cell_length_a 18.1111 _cell_length_b 18.1111 _cell_length_c 8.4619 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 120 _cell_volume 2403.743 _exptl_crystal_density_diffrn 2.622 _symmetry_space_group_name_H-M 'P 63' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x-y,x,1/2+z' '-y,x-y,z' '-x,-y,1/2+z' '-x+y,-x,z' 'y,-x+y,1/2+z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv Si(1) 0.83210 0.84060 0.19390 0.01100 Si(2) 0.66550 0.66520 0.79390 0.01060 Si(3) 0.65780 0.49400 0.17840 0.01110 Si(4) 0.50390 0.67750 0.17780 0.01160 Al(1) 0.83030 0.83810 0.81140 0.01080 Al(2) 0.66830 0.66820 0.18340 0.01100 Al(3) 0.65540 0.49150 0.79610 0.01090 Al(4) 0.50140 0.67610 0.79620 0.01100 K(1) 0.00000 0.00000 0.48620 0.02010 K(2) 0.66667 0.33333 0.50520 0.02080 K(3) 0.33333 0.66667 0.50480 0.02170 K(4) 0.47760 0.00470 0.49160 0.02300 K(5) 0.66650 0.81260 0.49460 0.02350 K(6) 0.80490 0.66750 0.49560 0.02330 O(1) 0.81610 0.85330 0.01010 0.01750 O(2) 0.66990 0.66500 0.98240 0.01980 O(3) 0.62720 0.47780 0.99510 0.01550 O(4) 0.51640 0.70650 0.99400 0.01710 O(5) 0.93080 0.86710 0.21780 0.01720 O(6) 0.73650 0.46760 0.77140 0.01630 O(7) 0.80090 0.39600 0.27240 0.01510 O(8) 0.90750 0.80840 0.79990 0.01830 O(9) 0.52500 0.76630 0.68520 0.01780 O(10) 0.43610 0.57710 0.18950 0.01930 O(11) 0.77020 0.74200 0.25070 0.01550 O(12) 0.89810 0.59480 0.75190 0.01600 O(13) 0.92560 0.35850 0.25580 0.01510 O(14) 0.35870 0.92970 0.73380 0.01610 O(15) 0.59440 0.90660 0.22530 0.01550 O(16) 0.73480 0.75840 0.72580 0.01680 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 Si(1) 0.01080 0.00990 0.01190 0.00490 -0.00060 0.00070 Si(2) 0.01060 0.01040 0.01090 0.00520 -0.00070 0.00040 Si(3) 0.01100 0.01020 0.01200 0.00520 0.00100 -0.00040 Si(4) 0.01180 0.01030 0.01260 0.00550 0.00010 -0.00160 Al(1) 0.01060 0.01060 0.01120 0.00520 0.00010 0.00170 Al(2) 0.01150 0.01080 0.01070 0.00550 -0.00020 0.00020 Al(3) 0.01220 0.01110 0.01050 0.00660 0.00020 -0.00010 Al(4) 0.01020 0.01040 0.01200 0.00500 0.00090 0.00060 K(1) 0.02060 0.02060 0.01920 0.01030 0.00000 0.00000 K(2) 0.02040 0.02040 0.02180 0.01020 0.00000 0.00000 K(3) 0.02090 0.02090 0.02330 0.01050 0.00000 0.00000 K(4) 0.02910 0.02130 0.02080 0.01410 -0.00070 0.00210 K(5) 0.02380 0.02640 0.01990 0.01230 0.00230 0.00070 K(6) 0.02290 0.02290 0.02400 0.01130 0.00390 0.00720 O(1) 0.01880 0.02000 0.01500 0.01060 -0.00110 -0.00080 O(2) 0.02780 0.02010 0.01210 0.01250 -0.00030 -0.00150 O(3) 0.01500 0.01710 0.01430 0.00780 -0.00030 0.00250 O(4) 0.02030 0.01590 0.01350 0.00790 0.00030 -0.00230 O(5) 0.01300 0.01670 0.02210 0.00740 -0.00220 0.00400 O(6) 0.01310 0.01670 0.02040 0.00830 0.00620 0.00360 O(7) 0.01520 0.01150 0.01930 0.00730 0.00360 -0.00060 O(8) 0.01990 0.02310 0.01660 0.01420 0.00530 0.00380 O(9) 0.01870 0.01880 0.02020 0.01270 0.00720 0.00650 O(10) 0.01980 0.01160 0.02270 0.00490 0.00520 -0.00110 O(11) 0.01480 0.01280 0.01730 0.00590 -0.00430 0.00020 O(12) 0.01380 0.01620 0.01370 0.00420 0.00240 -0.00280 O(13) 0.01560 0.02280 0.01190 0.01350 -0.00290 -0.00280 O(14) 0.01900 0.01220 0.01880 0.00920 0.00400 0.00260 O(15) 0.01080 0.01310 0.01750 0.00230 0.00170 -0.00390 O(16) 0.01720 0.01500 0.01590 0.00620 -0.00240 -0.00050