Synthetic and structural experiments on yttrium, cerium and magnesium trimethylsilylmethyls and their reaction products with nitriles; with a note on two cerium beta-diketiminates.
Avent, Anthony G.; Caro, Catherine F.; Hitchcock, Peter B.; Lappert, Michael F.; Li, Zhengning; Wei, Xue-Hong; Dalton transactions (Cambridge, England : 2003)  (2004) 1567–1577; doi:10.1039/b316695n

data_7013955
_publ_section_title
;
 Synthetic and structural experiments on yttrium, cerium and magnesium
 trimethylsilylmethyls and their reaction products with nitriles; with
 a note on two cerium beta-diketiminates.
;
_journal_issue                   10
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              1567
_journal_page_last               1577
_journal_paper_doi               10.1039/b316695n
_journal_year                    2004
_chemical_compound_source        'synthesis as described'
_chemical_formula_moiety         'C21 H57 Si6 Y1'
_chemical_formula_sum            'C21 H57 Si6 Y'
_chemical_formula_weight         567.12
_chemical_name_common            '[Y{CH(SiMe3)2}3]''
_chemical_name_systematic
;
?
;
_space_group_IT_number           159
_symmetry_cell_setting           hexagonal
_symmetry_Int_Tables_number      159
_symmetry_space_group_name_Hall  'P 3 -2c'
_symmetry_space_group_name_H-M   'P 3 1 c'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_conform_dict_location     ftp://ftp.iucr.org/cifdics/cif_core.dic
_audit_conform_dict_name         cif_core.dic
_audit_conform_dict_version      2.1
_audit_creation_date             2001-12-03T16:00:34-00:00
_audit_creation_method           'WinGX routine CIF_UPDATE'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                120
_cell_formula_units_Z            2
_cell_length_a                   16.2345(10)
_cell_length_b                   16.2345(10)
_cell_length_c                   8.6294(3)
_cell_measurement_reflns_used    6016
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      25.028
_cell_measurement_theta_min      4.076
_cell_measurement_wavelength     0.71073
_cell_volume                     1969.65(18)
_computing_cell_refinement       'HKL Scalepack (Otwinowski & Minor 1997)'
_computing_data_reduction
'HKL Denzo and Scalepack (Otwinowski & Minor 1997)'
_computing_molecular_graphics    'Ortep-3 for Windows (Farrugia, 1997)'
_computing_publication_material  'WinGX publication routines (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device       KappaCCD
_diffrn_measurement_method       CCD
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0673
_diffrn_reflns_av_unetI/netI     0.0532
_diffrn_reflns_limit_h_max       19
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       7
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            9004
_diffrn_reflns_theta_full        25.02
_diffrn_reflns_theta_max         25.02
_diffrn_reflns_theta_min         4.35
_exptl_absorpt_coefficient_mu    1.669
_exptl_absorpt_correction_T_max  0.835
_exptl_absorpt_correction_T_min  0.712
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
[c.f. r.h. blessing, acta cryst. (1995), a51, 33-38]
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    0.956
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             612
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.1
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.814
_refine_diff_density_min         -0.433
_refine_diff_density_rms         0.071
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.009(11)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.102
_refine_ls_hydrogen_treatment    riding
_refine_ls_matrix_type           full
_refine_ls_number_parameters     85
_refine_ls_number_reflns         2180
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.102
_refine_ls_R_factor_all          0.0582
_refine_ls_R_factor_gt           0.0475
_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^)+(0.0526P)^2^+2.0790P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1144
_refine_ls_wR_factor_ref         0.1193
_reflns_number_gt                1927
_reflns_number_total             2180
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b316695n.txt
_cod_data_source_block           (1)-dec101
_cod_original_sg_symbol_H-M      P31c
_cod_database_code               7013955