Ethylene Complexes of the Early Transition Metals: Crystal Structures of [HfEt4(C2H4)2−] and the Negative-Oxidation-State Species [TaHEt(C2H4)33−] and [WH(C2H4)43−]
Morse, Paige M.; Shelby, Quinetta D.; Kim, Do Young; Girolami, Gregory S.; Organometallics 27 (2008) 984–; doi:10.1021/om701189e

data_4070985
_publ_section_title
;
 Ethylene Complexes of the Early Transition Metals: Crystal Structures of
 [HfEt4(C2H4)2&#x2212;] and the Negative-Oxidation-State Species
 [TaHEt(C2H4)33&#x2212;] and [WH(C2H4)43&#x2212;]
;
_journal_issue                   5
_journal_name_full               Organometallics
_journal_page_first              984
_journal_paper_doi               10.1021/om701189e
_journal_volume                  27
_journal_year                    2008
_chemical_formula_sum            'C22 H56 Hf Li2 N4'
_chemical_formula_weight         569.08
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           61
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            16
_cell_length_a                   21.610(3)
_cell_length_b                   17.342(2)
_cell_length_c                   32.154(4)
_cell_measurement_reflns_used    1023
_cell_measurement_temperature    193(2)
_cell_measurement_theta_max      28.1
_cell_measurement_theta_min      1.63
_cell_volume                     12050(3)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      193(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_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  0.0781
_diffrn_reflns_av_sigmaI/netI    0.0957
_diffrn_reflns_limit_h_max       28
_diffrn_reflns_limit_h_min       -28
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       -22
_diffrn_reflns_limit_l_max       42
_diffrn_reflns_limit_l_min       -42
_diffrn_reflns_number            109674
_diffrn_reflns_theta_full        28.10
_diffrn_reflns_theta_max         28.10
_diffrn_reflns_theta_min         1.63
_exptl_absorpt_coefficient_mu    3.475
_exptl_absorpt_correction_T_max  0.675
_exptl_absorpt_correction_T_min  0.614
_exptl_absorpt_correction_type   integration
_exptl_crystal_density_diffrn    1.255
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             4704
_exptl_crystal_size_max          0.32
_exptl_crystal_size_mid          0.32
_exptl_crystal_size_min          0.20
_refine_diff_density_max         1.201
_refine_diff_density_min         -0.635
_refine_diff_density_rms         0.072
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.714
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     623
_refine_ls_number_reflns         14669
_refine_ls_number_restraints     148
_refine_ls_restrained_S_all      0.711
_refine_ls_R_factor_all          0.0683
_refine_ls_R_factor_gt           0.0242
_refine_ls_shift/su_max          0.005
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0100P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0370
_refine_ls_wR_factor_ref         0.0391
_reflns_number_gt                7554
_reflns_number_total             14669
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            om701189e-file003.cif
_cod_data_source_block           g99oface
_cod_original_cell_volume        12051(3)
_cod_database_code               4070985