Polymorphism in secondary squaramides: on the importance of π-interactions involving the four membered ring
Prohens, Rafel; Portell, Anna; Vallcorba, Oriol; Font-Bardia, Mercè; Bauzá, Antonio; Frontera, Antonio; CrystEngComm 20 (2018) 237–; doi:10.1039/C7CE01945A

data_7229638
_publ_section_title
;
 Polymorphism in secondary squaramides: on the importance of
 \p-interactions involving the four membered ring
;
_journal_issue                   2
_journal_name_full               CrystEngComm
_journal_page_first              237
_journal_paper_doi               10.1039/C7CE01945A
_journal_volume                  20
_journal_year                    2018
_chemical_formula_moiety         'C12 H22 N4 O2'
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_chemical_name_systematic        N,N?-bis(2-(dimethylamino)ethyl)squaramide
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_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_symmetry_space_group_name_Hall  '-P 2ybc'
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;
2017-11-07 deposited with the CCDC.
2017-12-01 downloaded from the CCDC.
;
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_diffrn_ambient_temperature      100(2)
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_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            43180
_diffrn_reflns_point_group_measured_fraction_full 0.998
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'Re-crystallisation from solvent: acetonitrile'
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_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
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; 
 w=1/[\s^2^(Fo^2^)+(0.0585P)^2^+0.6591P] 
 where P=(Fo^2^+2Fc^2^)/3 
;
_refine_ls_weighting_scheme      calc
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_reflns_number_total             3866
_reflns_threshold_expression     'I > 2\s(I)'
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_cod_depositor_comments
'Adding full bibliography for 7229635--7229638.cif.'
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