Ether and crown ether adduct complexes of sodium and potassium cyclopentadienide and methylcyclopentadienide—molecular structures of [Na(dme)Cp]∞ , [K(dme)0.5Cp]∞ , [Na(15-crown-5)Cp], [Na(18-crown-6)CpMe] and the “naked Cp−” complex [K(15-crown-5)2][Cp]
Marcus L. Cole; Cameron Jones; Peter C. Junk; J. Chem. Soc., Dalton Trans.  (2002) 896–905; doi:10.1039/b109124g

data_7011209
_publ_section_title
;
 Ether and crown ether adduct complexes of sodium and potassium
 cyclopentadienide and methylcyclopentadienide---molecular structures
 of [Na(dme)Cp]\\infty , [K(dme)0.5Cp]\\infty , [Na(15-crown-5)Cp],
 [Na(18-crown-6)CpMe] and the &#x201C;naked Cp&#x2212;&#x201D; complex
 [K(15-crown-5)2][Cp]
;
_journal_issue                   6
_journal_name_full               'J. Chem. Soc., Dalton Trans.'
_journal_page_first              896
_journal_page_last               905
_journal_paper_doi               10.1039/b109124g
_journal_year                    2002
_chemical_formula_sum            'C18 H31 Na O6'
_chemical_formula_weight         366.42
_space_group_IT_number           33
_symmetry_space_group_name_Hall  'P 2c -2n'
_symmetry_space_group_name_H-M   'P n a 21'
_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            4
_cell_length_a                   19.623(3)
_cell_length_b                   9.8461(17)
_cell_length_c                   10.8445(18)
_cell_measurement_temperature    296(2)
_cell_volume                     2095.3(6)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_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  0.0783
_diffrn_reflns_av_sigmaI/netI    0.0575
_diffrn_reflns_limit_h_max       21
_diffrn_reflns_limit_h_min       -21
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       7
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            8839
_diffrn_reflns_theta_full        23.20
_diffrn_reflns_theta_max         23.20
_diffrn_reflns_theta_min         2.08
_exptl_absorpt_coefficient_mu    0.103
_exptl_absorpt_correction_T_max  0.9818
_exptl_absorpt_correction_T_min  0.9699
_exptl_crystal_density_diffrn    1.162
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             792
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.18
_refine_diff_density_max         0.294
_refine_diff_density_min         -0.206
_refine_diff_density_rms         0.051
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.1(12)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.068
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     227
_refine_ls_number_reflns         2639
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.068
_refine_ls_R_factor_all          0.1129
_refine_ls_R_factor_gt           0.0862
_refine_ls_shift/su_max          0.012
_refine_ls_shift/su_mean         0.002
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1615P)^2^+0.4594P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2428
_refine_ls_wR_factor_ref         0.2734
_reflns_number_gt                1755
_reflns_number_total             2639
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b109124g.txt
_cod_data_source_block
COMPOUND_8#d:\junkie\xtals\bonocx\marcus\nacpme18\pj305
_cod_original_cell_volume        2095.2(6)
_cod_database_code               7011209