A double helix is the repeating unit in a luminescent calcium 5-aminoisophthalate supramolecular edifice with water-filled hexagonal channels.
Murugavel, Ramaswamy; Kumar, Parimal; Walawalkar, Mrinalini G.; Mathialagan, Ramyaa; Inorganic chemistry 46 (2007) 6828–6830; doi:10.1021/ic070113k

data_4339847
_publ_section_title
;
 A double helix is the repeating unit in a luminescent calcium
 5-aminoisophthalate supramolecular edifice with water-filled hexagonal
 channels.
;
_journal_issue                   17
_journal_name_full               'Inorganic chemistry'
_journal_page_first              6828
_journal_page_last               6830
_journal_paper_doi               10.1021/ic070113k
_journal_volume                  46
_journal_year                    2007
_chemical_formula_moiety         'C8 H15.66 Ca1 N1 O9.33'
_chemical_formula_sum            'C8 H15.67 Ca N O9.33'
_chemical_formula_weight         315.30
_chemical_name_common            CALCIUM-5-AMINOISOPHTHALATE
_chemical_name_systematic
;
 ?
;
_space_group_IT_number           148
_symmetry_cell_setting           trigonal
_symmetry_space_group_name_Hall  '-R 3'
_symmetry_space_group_name_H-M   'R -3 :H'
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_cell_formula_units_Z            18
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_cell_length_c                   13.2750(3)
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_cell_measurement_temperature    151(2)
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_cell_volume                     6459.2(2)
_computing_molecular_graphics    'Ortep-3 for Windows (Farrugia, 1997)'
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_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SIR92 (Giacovazzo et al, 1993)'
_diffrn_ambient_temperature      151(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
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_diffrn_reflns_limit_h_min       -33
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_exptl_absorpt_coefficient_mu    0.478
_exptl_absorpt_correction_T_max  0.9628
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_exptl_crystal_colour            'PALE BROWN'
_exptl_crystal_density_diffrn    1.459
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       NEEDLE
_exptl_crystal_F_000             2976
_exptl_crystal_size_max          0.10
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_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
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'calc w=1/[\s^2^(Fo^2^)+(0.1717P)^2^+18.6589P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
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_reflns_threshold_expression     >2sigma(I)
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_cod_original_cell_volume        6459.1(2)
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