#------------------------------------------------------------------------------ #$Date: 2025-02-21 04:59:15 +0200 (Fri, 21 Feb 2025) $ #$Revision: 297815 $ #$URL: file:///home/coder/svn-repositories/cod/cif/2/31/27/2312758.cif $ #------------------------------------------------------------------------------ # # This file is available in the Crystallography Open Database (COD), # http://www.crystallography.net/. The original data for this entry # were provided by IUCr Journals, http://journals.iucr.org/. # # The file may be used within the scientific community so long as # proper attribution is given to the journal article from which the # data were obtained. # data_2312758 loop_ _publ_author_name 'Kahlenberg, Volker' _publ_section_title ; Rb2Ca2Si2O7: a new alkali alkaline-earth silicate based on [Si2O7]6- anions. ; _journal_coeditor_code EF3065 _journal_issue 3 _journal_name_full 'Acta crystallographica. Section C, Structural chemistry' _journal_paper_doi 10.1107/S2053229625001196 _journal_volume 81 _journal_year 2025 _chemical_formula_iupac 'Rb2 Ca2 Si2 O7' _chemical_formula_sum 'Ca2 O7 Rb2 Si2' _chemical_formula_weight 419.28 _chemical_name_systematic ; Dirubidium dicalcium pyrosilicate ; _space_group_IT_number 59 _space_group_name_Hall '-P 2ab 2a' _space_group_name_H-M_alt 'P m m n :2' _symmetry_cell_setting orthorhombic _symmetry_space_group_name_H-M 'P m m n :2' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _audit_conform_dict_name cif_core.dic _audit_conform_dict_version 2.4.3 _audit_creation_method 'WinGX routine CIF_UPDATE' _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_formula_units_Z 4 _cell_length_a 5.7281(6) _cell_length_b 13.8361(13) _cell_length_c 9.9233(11) _cell_measurement_reflns_used 2430 _cell_measurement_temperature 193(2) _cell_measurement_theta_max 30.398 _cell_measurement_theta_min 4.995 _cell_volume 786.47(14) _computing_cell_refinement ; CrysAlis PRO (Rigaku OD, 2020) ; _computing_data_collection ; CrysAlis PRO (Rigaku OD, 2020) ; _computing_data_reduction ; CrysAlis PRO (Rigaku OD, 2020) ; _computing_structure_refinement ; SHELXL97 (Sheldrick, 2008) ; _computing_structure_solution ; SIR2002 (Burla et al., 2003) ; _diffrn_ambient_temperature 193(2) _diffrn_detector 'CCD plate' _diffrn_detector_area_resol_mean 10.3575 _diffrn_measured_fraction_theta_full 0.997 _diffrn_measured_fraction_theta_max 0.997 _diffrn_measurement_device 'four-circle diffractometer' _diffrn_measurement_device_type 'Rigaku Xcalibur Ruby Gemini ultra' _diffrn_measurement_method '\w scans' _diffrn_radiation_monochromator graphite _diffrn_radiation_probe x-ray _diffrn_radiation_type MoK\a _diffrn_radiation_wavelength 0.71073 _diffrn_reflns_av_R_equivalents 0.0585 _diffrn_reflns_av_unetI/netI 0.0239 _diffrn_reflns_limit_h_max 7 _diffrn_reflns_limit_h_min -7 _diffrn_reflns_limit_k_max 17 _diffrn_reflns_limit_k_min -17 _diffrn_reflns_limit_l_max 12 _diffrn_reflns_limit_l_min -12 _diffrn_reflns_number 10870 _diffrn_reflns_theta_full 26.36 _diffrn_reflns_theta_max 26.36 _diffrn_reflns_theta_min 3.59 _diffrn_source 'fine-focus sealed X-ray tube' _exptl_absorpt_coefficient_mu 14.051 _exptl_absorpt_correction_T_max 0.675 _exptl_absorpt_correction_T_min 0.109 _exptl_absorpt_correction_type analytical _exptl_absorpt_process_details ; [CrysAlis PRO (Rigaku OD, 2020), based on expressions derived by Clark & Reid (1995)] ; _exptl_crystal_colour colourless _exptl_crystal_density_diffrn 3.541 _exptl_crystal_density_method 'not measured' _exptl_crystal_description 'thin plate' _exptl_crystal_F_000 792 _exptl_crystal_size_max 0.323 _exptl_crystal_size_mid 0.1 _exptl_crystal_size_min 0.036 _refine_diff_density_max 0.933 _refine_diff_density_min -0.746 _refine_ls_extinction_coef 0.0075(4) _refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^ _refine_ls_extinction_method ; SHELXL97 (Sheldrick, 2008) ; _refine_ls_goodness_of_fit_ref 1.067 _refine_ls_matrix_type full _refine_ls_number_parameters 78 _refine_ls_number_reflns 929 _refine_ls_number_restraints 0 _refine_ls_restrained_S_all 1.067 _refine_ls_R_factor_all 0.0391 _refine_ls_R_factor_gt 0.029 _refine_ls_shift/su_max 0 _refine_ls_shift/su_mean 0 _refine_ls_structure_factor_coef Fsqd _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.0180P)^2^+4.8532P] where P=(Fo^2^+2Fc^2^)/3' _refine_ls_weighting_scheme calc _refine_ls_wR_factor_gt 0.0621 _refine_ls_wR_factor_ref 0.0668 _reflns_number_gt 777 _reflns_number_total 929 _reflns_threshold_expression >2\s(I) _iucr_refine_instructions_details ; TITL Pmmn -80 C face absortion correction CELL 0.71073 5.7281 13.8361 9.9233 90.000 90.000 90.000 ZERR 2 0.0006 0.0013 0.0011 0.000 0.000 0.000 LATT 1 SYMM 0.50000 - X , 0.50000 - Y , Z SYMM 0.50000 + X , - Y , - Z SYMM - X , 0.50000 + Y , - Z SFAC Ca O Rb Si UNIT 8 28 8 8 SHEL 999 0.80 L.S. 10 FMAP 2 PLAN 10 TEMP -80 ACTA BOND EXYZ RB3 CA3 EADP RB3 CA3 REM M1, M2 = Rb; M3 = 50% Ca+ 50% Rb; M4, M5: Ca WGHT 0.018000 4.853200 EXTI 0.007454 FVAR 2.35735 RB1 3 0.750000 0.104801 0.085306 10.50000 0.01067 0.02042 = 0.01042 0.00007 0.00000 0.00000 RB2 3 0.250000 0.250000 0.258841 10.25000 0.01411 0.01005 = 0.01296 0.00000 0.00000 0.00000 RB3 3 0.250000 0.097994 0.586929 10.25000 0.01611 0.03449 = 0.01134 -0.00712 0.00000 0.00000 CA3 1 0.250000 0.097994 0.586929 10.25000 0.01611 0.03449 = 0.01134 -0.00712 0.00000 0.00000 CA4 1 0.750000 0.250000 0.749213 10.25000 0.00986 0.00462 = 0.00940 0.00000 0.00000 0.00000 CA5 1 0.250000 0.510806 0.248852 10.50000 0.01166 0.00587 = 0.00877 0.00014 0.00000 0.00000 SI1 4 0.750000 0.136234 0.418584 10.50000 0.02082 0.00958 = 0.01071 -0.00025 0.00000 0.00000 SI2 4 0.250000 0.139585 0.919180 10.50000 0.00698 0.00546 = 0.01102 0.00217 0.00000 0.00000 O1 2 0.018321 0.127374 0.827959 11.00000 0.01366 0.01891 = 0.03069 0.00766 -0.01117 -0.00709 O2 2 0.250000 0.073243 1.051980 10.50000 0.01671 0.01414 = 0.01871 0.00592 0.00000 0.00000 O3 2 0.250000 0.250000 0.982472 10.25000 0.04006 0.01050 = 0.01550 0.00000 0.00000 0.00000 O4 2 0.524235 0.082067 0.360358 11.00000 0.04983 0.02801 = 0.04955 0.00475 -0.02529 -0.01629 O5 2 0.750000 0.250000 0.359823 10.25000 0.01972 0.00999 = 0.00612 0.00000 0.00000 0.00000 O6 2 0.750000 0.136079 0.579340 10.50000 0.06987 0.01182 = 0.01509 -0.00081 0.00000 0.00000 HKLF 4 REM Pmmn -80 C face absortion correction REM R1 = 0.0290 for 777 Fo > 4sig(Fo) and 0.0391 for all 929 data REM 78 parameters refined using 0 restraints END WGHT 0.0175 4.8861 REM Highest difference peak 0.933, deepest hole -0.746, 1-sigma level 0.150 Q1 1 0.3449 0.0606 0.6020 11.00000 0.05 0.93 Q2 1 0.6419 0.1697 0.4657 11.00000 0.05 0.75 Q3 1 0.1434 0.2500 0.9405 10.50000 0.05 0.69 Q4 1 0.7500 0.0606 0.0223 10.50000 0.05 0.66 Q5 1 0.2500 0.0060 1.0456 10.50000 0.05 0.55 Q6 1 0.5047 0.1017 0.4394 11.00000 0.05 0.54 Q7 1 0.8169 0.2500 0.2980 10.50000 0.05 0.53 Q8 1 0.2500 0.0938 1.0986 10.50000 0.05 0.50 Q9 1 0.5758 0.1531 0.5721 11.00000 0.05 0.49 Q10 1 0.2500 0.2999 0.2963 10.50000 0.05 0.48 ; _cod_data_source_file ef3065.cif _cod_data_source_block LT _cod_original_sg_symbol_H-M 'P m m n' _cod_database_code 2312758 loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x+1/2, -y+1/2, z' 'x+1/2, -y, -z' '-x, y+1/2, -z' '-x, -y, -z' 'x-1/2, y-1/2, -z' '-x-1/2, y, z' 'x, -y-1/2, z' loop_ _atom_site_type_symbol _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_calc_flag _atom_site_refinement_flags _atom_site_occupancy _atom_site_symmetry_multiplicity _atom_site_disorder_assembly _atom_site_disorder_group Rb Rb1 0.75 0.10480(4) 0.08531(6) 0.0138(2) Uani d S 1 2 . . Rb Rb2 0.25 0.25 0.25884(8) 0.0124(2) Uani d S 1 4 . . Rb Rb3 0.25 0.09799(7) 0.58693(8) 0.0206(2) Uani d SP 0.5 2 . . Ca Ca3 0.25 0.09799(7) 0.58693(8) 0.0206(2) Uani d SP 0.5 2 . . Ca Ca4 0.75 0.25 0.74921(15) 0.0080(4) Uani d S 1 4 . . Ca Ca5 0.25 0.51081(8) 0.24885(11) 0.0088(3) Uani d S 1 2 . . Si Si1 0.75 0.13623(12) 0.41858(17) 0.0137(4) Uani d S 1 2 . . Si Si2 0.25 0.13959(11) 0.91918(16) 0.0078(3) Uani d S 1 2 . . O O1 0.0183(5) 0.1274(2) 0.8280(3) 0.0211(7) Uani d . 1 1 . . O O2 0.25 0.0732(3) 1.0520(4) 0.0165(9) Uani d S 1 2 . . O O3 0.25 0.25 0.9825(6) 0.0220(15) Uani d S 1 4 . . O O4 0.5242(7) 0.0821(3) 0.3604(4) 0.0425(11) Uani d . 1 1 . . O O5 0.75 0.25 0.3598(6) 0.0119(12) Uani d S 1 4 . . O O6 0.75 0.1361(3) 0.5793(5) 0.0323(13) Uani d S 1 2 . . 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 Rb1 0.0107(3) 0.0204(3) 0.0104(3) 0 0 0.0001(2) Rb2 0.0141(4) 0.0100(4) 0.0130(4) 0 0 0 Rb3 0.0161(4) 0.0345(5) 0.0113(4) 0 0 -0.0071(4) Ca3 0.0161(4) 0.0345(5) 0.0113(4) 0 0 -0.0071(4) Ca4 0.0099(8) 0.0046(7) 0.0094(8) 0 0 0 Ca5 0.0117(6) 0.0059(5) 0.0088(6) 0 0 0.0001(4) Si1 0.0208(9) 0.0096(8) 0.0107(8) 0 0 -0.0003(6) Si2 0.0070(7) 0.0055(7) 0.0110(8) 0 0 0.0022(6) O1 0.0137(15) 0.0189(15) 0.0307(19) -0.0071(13) -0.0112(14) 0.0077(14) O2 0.017(2) 0.014(2) 0.019(2) 0 0 0.0059(18) O3 0.040(4) 0.010(3) 0.015(3) 0 0 0 O4 0.050(3) 0.0280(19) 0.050(2) -0.0163(19) -0.025(2) 0.0048(18) O5 0.020(3) 0.010(3) 0.006(3) 0 0 0 O6 0.070(4) 0.012(2) 0.015(2) 0 0 -0.0008(18) loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source Ca Ca 0.2262 0.3064 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' O O 0.0106 0.006 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' Rb Rb -0.9393 2.9676 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' Si Si 0.0817 0.0704 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' loop_ _exptl_crystal_face_index_h _exptl_crystal_face_index_k _exptl_crystal_face_index_l _exptl_crystal_face_perp_dist -2 -13 10 0.095 1 18 -8 0.1266 -5 -4 4 0.0813 -7 8 1 0.0171 7 -8 -5 0.0316 7 -7 4 0.016 -7 7 -4 0.0164 2 0 14 0.0457 -3 0 -13 0.0338 5 0 -10 0.0524 loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle _geom_angle_publ_flag O2 Rb1 O2 5_656 1_554 79.29(8) ? O2 Rb1 O2 5_656 1_654 79.29(8) ? O2 Rb1 O2 1_554 1_654 158.35(17) ? O2 Rb1 O1 5_656 7_654 71.27(9) ? O2 Rb1 O1 1_554 7_654 54.21(10) ? O2 Rb1 O1 1_654 7_654 115.00(10) ? O2 Rb1 O1 5_656 1_654 71.27(9) ? O2 Rb1 O1 1_554 1_654 115.00(10) ? O2 Rb1 O1 1_654 1_654 54.21(10) ? O1 Rb1 O1 7_654 1_654 61.71(11) ? O2 Rb1 O4 5_656 . 110.14(10) ? O2 Rb1 O4 1_554 . 70.62(11) ? O2 Rb1 O4 1_654 . 120.31(11) ? O1 Rb1 O4 7_654 . 123.94(9) ? O1 Rb1 O4 1_654 . 174.34(10) ? O2 Rb1 O4 5_656 7_755 110.14(10) ? O2 Rb1 O4 1_554 7_755 120.31(11) ? O2 Rb1 O4 1_654 7_755 70.62(11) ? O1 Rb1 O4 7_654 7_755 174.34(10) ? O1 Rb1 O4 1_654 7_755 123.94(9) ? O4 Rb1 O4 . 7_755 50.41(15) ? O3 Rb2 O4 1_554 8_565 109.76(9) ? O3 Rb2 O4 1_554 7_655 109.76(9) ? O4 Rb2 O4 8_565 7_655 140.49(17) ? O3 Rb2 O4 1_554 . 109.76(9) ? O4 Rb2 O4 8_565 . 102.46(14) ? O4 Rb2 O4 7_655 . 63.62(15) ? O3 Rb2 O4 1_554 2 109.76(8) ? O4 Rb2 O4 8_565 2 63.62(15) ? O4 Rb2 O4 7_655 2 102.46(14) ? O4 Rb2 O4 . 2 140.49(17) ? O3 Rb2 O5 1_554 . 109.28(10) ? O4 Rb2 O5 8_565 . 52.47(7) ? O4 Rb2 O5 7_655 . 112.70(10) ? O4 Rb2 O5 . . 52.47(7) ? O4 Rb2 O5 2 . 112.70(10) ? O3 Rb2 O5 1_554 1_455 109.28(10) ? O4 Rb2 O5 8_565 1_455 112.70(10) ? O4 Rb2 O5 7_655 1_455 52.47(7) ? O4 Rb2 O5 . 1_455 112.70(10) ? O4 Rb2 O5 2 1_455 52.47(7) ? O5 Rb2 O5 . 1_455 141.4(2) ? O3 Rb2 O2 1_554 1_554 49.99(7) ? O4 Rb2 O2 8_565 1_554 144.54(9) ? O4 Rb2 O2 7_655 1_554 67.67(10) ? O4 Rb2 O2 . 1_554 67.67(10) ? O4 Rb2 O2 2 1_554 144.54(9) ? O5 Rb2 O2 . 1_554 102.26(6) ? O5 Rb2 O2 1_455 1_554 102.26(6) ? O3 Rb2 O2 1_554 2_554 49.99(7) ? O4 Rb2 O2 8_565 2_554 67.67(10) ? O4 Rb2 O2 7_655 2_554 144.54(9) ? O4 Rb2 O2 . 2_554 144.54(9) ? O4 Rb2 O2 2 2_554 67.67(10) ? O5 Rb2 O2 . 2_554 102.26(6) ? O5 Rb2 O2 1_455 2_554 102.26(6) ? O2 Rb2 O2 1_554 2_554 99.98(15) ? O4 Rb3 O4 7_655 . 69.62(16) ? O4 Rb3 O1 7_655 7_655 172.97(10) ? O4 Rb3 O1 . 7_655 116.39(10) ? O4 Rb3 O1 7_655 . 116.39(10) ? O4 Rb3 O1 . . 172.97(10) ? O1 Rb3 O1 7_655 . 57.36(12) ? O4 Rb3 O4 7_655 3_456 79.70(12) ? O4 Rb3 O4 . 3_456 109.78(8) ? O1 Rb3 O4 7_655 3_456 100.79(11) ? O1 Rb3 O4 . 3_456 75.67(10) ? O4 Rb3 O4 7_655 5_656 109.78(8) ? O4 Rb3 O4 . 5_656 79.70(12) ? O1 Rb3 O4 7_655 5_656 75.67(10) ? O1 Rb3 O4 . 5_656 100.79(11) ? O4 Rb3 O4 3_456 5_656 53.86(16) ? O4 Rb3 O6 7_655 . 123.69(12) ? O4 Rb3 O6 . . 55.40(12) ? O1 Rb3 O6 7_655 . 61.57(11) ? O1 Rb3 O6 . . 117.88(11) ? O4 Rb3 O6 3_456 . 127.43(12) ? O4 Rb3 O6 5_656 . 73.58(12) ? O4 Rb3 O6 7_655 1_455 55.39(12) ? O4 Rb3 O6 . 1_455 123.69(12) ? O1 Rb3 O6 7_655 1_455 117.88(11) ? O1 Rb3 O6 . 1_455 61.57(11) ? O4 Rb3 O6 3_456 1_455 73.58(12) ? O4 Rb3 O6 5_656 1_455 127.43(12) ? O6 Rb3 O6 . 1_455 158.94(18) ? O6 Ca4 O6 . 2_655 86.2(2) ? O6 Ca4 O1 . 8_665 135.64(10) ? O6 Ca4 O1 2_655 8_665 75.93(12) ? O6 Ca4 O1 . 7_655 75.93(12) ? O6 Ca4 O1 2_655 7_655 135.64(10) ? O1 Ca4 O1 8_665 7_655 142.31(18) ? O6 Ca4 O1 . 1_655 75.93(12) ? O6 Ca4 O1 2_655 1_655 135.64(10) ? O1 Ca4 O1 8_665 1_655 89.08(14) ? O1 Ca4 O1 7_655 1_655 78.90(14) ? O6 Ca4 O1 . 2 135.64(10) ? O6 Ca4 O1 2_655 2 75.93(12) ? O1 Ca4 O1 8_665 2 78.90(14) ? O1 Ca4 O1 7_655 2 89.08(14) ? O1 Ca4 O1 1_655 2 142.31(18) ? O2 Ca5 O4 2_554 2 97.30(13) ? O2 Ca5 O4 2_554 8_565 97.30(13) ? O4 Ca5 O4 2 8_565 85.6(2) ? O2 Ca5 O1 2_554 6_666 94.14(12) ? O4 Ca5 O1 2 6_666 168.32(13) ? O4 Ca5 O1 8_565 6_666 95.29(14) ? O2 Ca5 O1 2_554 4_556 94.14(12) ? O4 Ca5 O1 2 4_556 95.29(14) ? O4 Ca5 O1 8_565 4_556 168.32(13) ? O1 Ca5 O1 6_666 4_556 81.50(16) ? O2 Ca5 O6 2_554 6_566 165.29(16) ? O4 Ca5 O6 2 6_566 93.48(13) ? O4 Ca5 O6 8_565 6_566 93.48(13) ? O1 Ca5 O6 6_666 6_566 74.85(11) ? O1 Ca5 O6 4_556 6_566 74.85(11) ? O6 Si1 O4 . . 111.10(19) ? O6 Si1 O4 . 7_755 111.10(19) ? O4 Si1 O4 . 7_755 107.6(3) ? O6 Si1 O5 . . 110.4(3) ? O4 Si1 O5 . . 108.26(18) ? O4 Si1 O5 7_755 . 108.26(18) ? O2 Si2 O1 . . 113.58(14) ? O2 Si2 O1 . 7_655 113.58(14) ? O1 Si2 O1 . 7_655 110.5(3) ? O2 Si2 O3 . . 102.5(3) ? O1 Si2 O3 . . 108.05(16) ? O1 Si2 O3 7_655 . 108.05(17) ? Si2 O3 Si2 . 2 135.3(4) ? Si1 O5 Si1 2_655 . 139.3(4) ? loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_site_symmetry_2 _geom_bond_distance _geom_bond_publ_flag Rb1 O2 5_656 2.815(4) ? Rb1 O2 1_554 2.9160(9) ? Rb1 O2 1_654 2.9160(9) ? Rb1 O1 7_654 2.997(3) ? Rb1 O1 1_654 2.997(3) ? Rb1 O4 . 3.037(4) ? Rb1 O4 7_755 3.037(4) ? Rb1 O5 . 3.385(4) ? Rb2 O3 1_554 2.742(6) ? Rb2 O4 8_565 2.980(4) ? Rb2 O4 7_655 2.980(4) ? Rb2 O4 . 2.980(4) ? Rb2 O4 2 2.980(4) ? Rb2 O5 . 3.0343(19) ? Rb2 O5 1_455 3.0343(19) ? Rb2 O2 1_554 3.193(4) ? Rb2 O2 2_554 3.193(4) ? Rb3 O4 7_655 2.752(5) ? Rb3 O4 . 2.752(5) ? Rb3 O1 7_655 2.765(4) ? Rb3 O1 . 2.765(4) ? Rb3 O4 3_456 2.855(4) ? Rb3 O4 5_656 2.855(4) ? Rb3 O6 . 2.9131(9) ? Rb3 O6 1_455 2.9131(9) ? Ca4 O6 . 2.308(5) ? Ca4 O6 2_655 2.308(5) ? Ca4 O1 8_665 2.419(3) ? Ca4 O1 7_655 2.419(3) ? Ca4 O1 1_655 2.419(3) ? Ca4 O1 2 2.419(3) ? Ca5 O2 2_554 2.274(4) ? Ca5 O4 2 2.312(4) ? Ca5 O4 8_565 2.312(4) ? Ca5 O1 6_666 2.355(3) ? Ca5 O1 4_556 2.355(3) ? Ca5 O6 6_566 2.431(5) ? Si1 O6 . 1.595(5) ? Si1 O4 . 1.602(4) ? Si1 O4 7_755 1.602(4) ? Si1 O5 . 1.679(2) ? Si2 O2 . 1.606(4) ? Si2 O1 . 1.615(3) ? Si2 O1 7_655 1.615(3) ? Si2 O3 . 1.652(3) ? O1 Si2 . 1.615(3) ? O1 Ca5 6_556 2.355(3) ? O1 Ca4 1_455 2.419(3) ? O1 Rb3 . 2.765(4) ? O1 Rb1 1_456 2.997(3) ? O2 Si2 . 1.606(4) ? O2 Ca5 2_556 2.274(4) ? O2 Rb1 5_656 2.815(4) ? O2 Rb1 1_556 2.9160(9) ? O2 Rb1 1_456 2.9160(9) ? O2 Rb2 1_556 3.193(4) ? O3 Si2 2 1.652(3) ? O3 Si2 . 1.652(3) ? O3 Rb2 1_556 2.742(6) ? O4 Si1 . 1.603(4) ? O4 Ca5 2 2.312(4) ? O4 Ca3 5_656 2.855(4) ? O4 Rb3 . 2.752(5) ? O4 Rb3 5_656 2.855(4) ? O4 Rb2 . 2.980(4) ? O4 Rb1 . 3.037(5) ? O5 Si1 2_655 1.679(2) ? O5 Si1 . 1.679(2) ? O5 Rb2 1_655 3.0343(19) ? O5 Rb2 . 3.0343(19) ? O5 Rb1 2_655 3.385(4) ? O5 Rb1 . 3.385(4) ? O6 Si1 . 1.595(5) ? O6 Ca4 . 2.308(4) ? O6 Ca5 6_656 2.431(5) ? O6 Rb3 1_655 2.9131(9) ? O6 Rb3 . 2.9131(9) ?