A Comparative Study of π-Arene-Bridged Lanthanum Arylamide and Aryloxide Dimers. Solution Behavior, Exchange Mechanisms, and X-ray Crystal Structures of La2(NH-2,6-iPr2C6H3)6, La(NH-2,6-iPr2C6H3)3(THF)3, and La(NH-2,6-iPr2C6H3)3(py)2
Garth R. Giesbrecht; John C. Gordon; David L. Clark; P. Jeffrey Hay; Brian L. Scott; C. Drew Tait; Journal of the American Chemical Society 126 (2004) 6387–6401; doi:10.1021/ja0398262

data_4112587
_publ_contact_author
;
John C. Gordon
MS J514
Los Alamos National Laboratory
Los Alamos, New Mexico  87545
;
_publ_contact_author_email       jgordon@lanl.gov
_publ_section_title
;
 A Comparative Study of \p-Arene-Bridged Lanthanum Arylamide and Aryloxide
 Dimers. Solution Behavior, Exchange Mechanisms, and X-ray Crystal
 Structures of La2(NH-2,6-iPr2C6H3)6, La(NH-2,6-iPr2C6H3)3(THF)3, and
 La(NH-2,6-iPr2C6H3)3(py)2
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              6387
_journal_page_last               6401
_journal_paper_doi               10.1021/ja0398262
_journal_volume                  126
_journal_year                    2004
_chemical_formula_sum            'C46 H64 La N5'
_chemical_formula_weight         825.93
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 112.122(11)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   16.013(6)
_cell_length_b                   14.159(5)
_cell_length_c                   21.202(6)
_cell_measurement_temperature    203(2)
_cell_volume                     4453(3)
_computing_cell_refinement       'Bruker SAINT (v. 5.00, Bruker 1998)'
_computing_data_collection       'Siemens SMART (v. 4.202, Siemens 1996)'
_computing_data_reduction        'Bruker SAINT (v. 5.00, Bruker 1998)'
_computing_molecular_graphics    'Bruker AXS SHEXTL (v. 5.10)'
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      203(2)
_diffrn_measured_fraction_theta_full 0.983
_diffrn_measured_fraction_theta_max 0.983
_diffrn_measurement_device_type  'Bruker P4/CCD'
_diffrn_measurement_method       '\f scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0190
_diffrn_reflns_av_sigmaI/netI    0.0245
_diffrn_reflns_limit_h_max       19
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       25
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            28486
_diffrn_reflns_theta_full        25.52
_diffrn_reflns_theta_max         25.52
_diffrn_reflns_theta_min         1.04
_diffrn_standards_decay_%        '< 2'
_exptl_absorpt_coefficient_mu    0.994
_exptl_absorpt_correction_T_max  0.8900
_exptl_absorpt_correction_T_min  0.7614
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'SADABS (Sheldrick, 1996)'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.232
_exptl_crystal_description       irregular
_exptl_crystal_F_000             1728
_exptl_crystal_size_max          0.29
_exptl_crystal_size_mid          0.21
_exptl_crystal_size_min          0.12
_refine_diff_density_max         0.678
_refine_diff_density_min         -0.394
_refine_diff_density_rms         0.055
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.423(8)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.164
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     956
_refine_ls_number_reflns         14478
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.164
_refine_ls_R_factor_all          0.0298
_refine_ls_R_factor_gt           0.0279
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0454P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0719
_refine_ls_wR_factor_ref         0.0727
_reflns_number_gt                14003
_reflns_number_total             14478
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja0398262si20031126_061303_3.cif
_cod_data_source_block           ccd728a
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               4112587