The structure of the decamethylborocenium cation: the most tightly-squeezed metallocene?
Voigt, Andreas; Filipponi, Silvia; Macdonald, Charles L. B.; Gorden, John D.; Cowley, Alan H.; Chemical Communications  (2000) 911–; doi:10.1039/b001271h

data_7110899
_publ_section_title
;
 The structure of the decamethylborocenium cation: the most
 tightly-squeezed metallocene?
;
_journal_issue                   11
_journal_name_full               'Chemical Communications'
_journal_page_first              911
_journal_paper_doi               10.1039/b001271h
_journal_year                    2000
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_chemical_formula_moiety         '[C20H30B] [AlCl4]'
_chemical_formula_structural     '[Cp*BCp*] [AlCl4] '
_chemical_formula_sum            'C20 H30 Al B Cl4'
_chemical_formula_weight         450.03
_chemical_melting_point          ?
_chemical_name_common            'decamethylborocenium tetrachloroaluminate'
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
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_cell_length_b                   13.611(3)
_cell_length_c                   20.493(4)
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_cell_measurement_temperature    153(2)
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_cell_measurement_theta_min      n/a
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_computing_structure_solution    'SHELXS-86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      153(2)
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_diffrn_measurement_method       '\w scans'
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_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
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_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0849P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
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_cod_data_source_file            b001271hsup1.cif
_cod_data_source_block           d
_cod_depositor_comments
;
The following automatic conversions were performed:

'_chemical_melting_point' value 'n/d' was changed to '?' - the value
is undefined or not given.

'_symmetry_cell_setting' value
'Monoclinic' changed to 'monoclinic' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 1891 2012-01-12 08:04:46Z andrius 

The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'n/a' was changed to '?' - the
value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.0849P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to
'w=1/[\s^2^(Fo^2^)+(0.0849P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_sg_symbol_H-M      P2(1)/n
_cod_database_code               7110899