Li2Ca2Si2O7: Structural, spectroscopic and computational studies on a sorosilicate
Kahlenberg, Volker; Brunello, Emanuele; Hejny, Clivia; Krüger, Hannes; Schmidmair, Daniela; Tribus, Martina; Többens, Daniel M.; Journal of Solid State Chemistry 225 (2015) 155–167; doi:10.1016/j.jssc.2014.12.009

data_1562016
_publ_section_title
;
 Li2Ca2Si2O7: Structural, spectroscopic and computational studies on a
 sorosilicate
;
_journal_name_full               'Journal of Solid State Chemistry'
_journal_page_first              155
_journal_page_last               167
_journal_paper_doi               10.1016/j.jssc.2014.12.009
_journal_volume                  225
_journal_year                    2015
_chemical_absolute_configuration ad
_chemical_formula_moiety         'O7 Si2, 2(Ca), 2(Li)'
_chemical_formula_sum            'Ca2 Li2 O7 Si2'
_chemical_formula_weight         262.22
_space_group_IT_number           178
_space_group_name_Hall           'P 61 2 (0 0 5)'
_space_group_name_H-M_alt        'P 61 2 2'
_symmetry_cell_setting           hexagonal
_symmetry_space_group_name_H-M   'P 61 2 2'
_atom_sites_solution_hydrogens   ' '
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                120
_cell_formula_units_Z            6
_cell_length_a                   5.09611(17)
_cell_length_b                   5.09611(17)
_cell_length_c                   41.2640(17)
_cell_measurement_reflns_used    2633
_cell_measurement_temperature    295(2)
_cell_measurement_theta_max      28.6775
_cell_measurement_theta_min      3.9506
_cell_volume                     928.07(6)
_computing_cell_refinement
;
        CrysAlisPro, Agilent Technologies,
        Version 1.171.37.31 (release 14-01-2014 CrysAlis171 .NET)
        (compiled Jan 14 2014,18:38:05)
;
_computing_data_collection
;
        CrysAlisPro, Agilent Technologies,
        Version 1.171.37.31 (release 14-01-2014 CrysAlis171 .NET)
        (compiled Jan 14 2014,18:38:05)
;
_computing_data_reduction
;
        CrysAlisPro, Agilent Technologies,
        Version 1.171.37.31 (release 14-01-2014 CrysAlis171 .NET)
        (compiled Jan 14 2014,18:38:05)
;
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SIR2002 (Burla et al., 2003)'
_diffrn_ambient_temperature      295(2)
_diffrn_detector                 'CCD plate'
_diffrn_detector_area_resol_mean 10.3575
_diffrn_measured_fraction_theta_full 0.986
_diffrn_measured_fraction_theta_max 0.986
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'Xcalibur, Ruby, Gemini ultra'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_UB_11      0.0980733
_diffrn_orient_matrix_UB_12      -0.0327214
_diffrn_orient_matrix_UB_13      -0.0091398
_diffrn_orient_matrix_UB_21      0.118838
_diffrn_orient_matrix_UB_22      0.0844725
_diffrn_orient_matrix_UB_23      0.0111518
_diffrn_orient_matrix_UB_31      -0.0458767
_diffrn_orient_matrix_UB_32      -0.1327874
_diffrn_orient_matrix_UB_33      0.0093434
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0327
_diffrn_reflns_av_unetI/netI     0.0207
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       5
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       52
_diffrn_reflns_limit_l_min       -37
_diffrn_reflns_number            5494
_diffrn_reflns_theta_full        28.68
_diffrn_reflns_theta_max         28.68
_diffrn_reflns_theta_min         4.62
_diffrn_source                   'Enhance (Mo) X-ray Source'
_exptl_absorpt_coefficient_mu    2.219
_exptl_absorpt_correction_T_max  0.832
_exptl_absorpt_correction_T_min  0.636
_exptl_absorpt_correction_type   analytical
_exptl_absorpt_process_details
;
        CrysAlisPro, Agilent Technologies,
        Version 1.171.37.31 (release 14-01-2014 CrysAlis171 .NET)
        (compiled Jan 14 2014,18:38:05)
Analytical numeric absorption correction using a multifaceted crystal
                        model based on expressions derived by R.C. Clark & J.S.
        (Clark, R. C. & Reid, J. S. (1995). Acta Cryst. A51, 887-897)
        Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    2.815
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       fragment
_exptl_crystal_F_000             780
_exptl_crystal_size_max          0.24
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.297
_refine_diff_density_min         -0.426
_refine_diff_density_rms         0.093
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.04(13)
_refine_ls_extinction_coef       0.0124(10)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.38
_refine_ls_hydrogen_treatment    noref
_refine_ls_matrix_type           full
_refine_ls_number_parameters     62
_refine_ls_number_reflns         780
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.38
_refine_ls_R_factor_all          0.0283
_refine_ls_R_factor_gt           0.026
_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^)+(0.0208P)^2^+1.2051P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.069
_refine_ls_wR_factor_ref         0.0697
_reflns_number_gt                738
_reflns_number_total             780
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            JSSC-2015-225-155.cif
_cod_data_source_block           kristall_2_rt
_cod_database_code               1562016