Alkynyl and Phosphonyl Substituted Nucleobases: A Case of Thermally Induced Conformational Polymorphism
Kumara Swamy, K. C.; Allu, Srinivasarao; Srinivas, Venu; Balaraman, E.; Kumar, K. V. P. Pavan; Crystal Growth & Design 11 (2011) 2302–; doi:10.1021/cg101737x

data_4500589
_publ_section_title
;
 Alkynyl and Phosphonyl Substituted Nucleobases: A Case of Thermally
 Induced Conformational Polymorphism
;
_journal_issue                   6
_journal_name_full               'Crystal Growth &amp; Design'
_journal_page_first              2302
_journal_paper_doi               10.1021/cg101737x
_journal_volume                  11
_journal_year                    2011
_chemical_formula_sum            'C15 H23 N5'
_chemical_formula_weight         273.38
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_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                 107.45(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   17.181(3)
_cell_length_b                   8.113(1)
_cell_length_c                   11.691(2)
_cell_measurement_reflns_used    2123
_cell_measurement_temperature    298(2)
_cell_volume                     1554.6(5)
_computing_cell_refinement       'CrysAlisPro, Oxford Diffraction Ltd.'
_computing_data_collection       'CrysAlisPro, Oxford Diffraction Ltd.'
_computing_data_reduction        'CrysAlisPro, Oxford Diffraction Ltd.'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Xcalibur, Eos, Gemini'
_diffrn_measurement_method       '\w scans'
_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  0.0229
_diffrn_reflns_av_sigmaI/netI    0.0298
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -20
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            5777
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         3.10
_diffrn_standards_decay_%        none
_diffrn_standards_interval_count 'not applicable'
_diffrn_standards_interval_time  'not applicable'
_diffrn_standards_number         'not applicable'
_exptl_absorpt_coefficient_mu    0.073
_exptl_absorpt_correction_T_max  0.9869
_exptl_absorpt_correction_T_min  0.9826
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'CrysAlisPro, Oxford Diffraction Ltd.'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.168
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             592
_exptl_crystal_size_max          0.24
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.18
_refine_diff_density_max         0.331
_refine_diff_density_min         -0.302
_refine_diff_density_rms         0.037
_refine_ls_extinction_coef       0.015(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.111
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     199
_refine_ls_number_reflns         2724
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.111
_refine_ls_R_factor_all          0.0764
_refine_ls_R_factor_gt           0.0530
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0958P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1539
_refine_ls_wR_factor_ref         0.1647
_reflns_number_gt                1844
_reflns_number_total             2724
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            cg101737x_si_002.cif
_cod_data_source_block           compd10
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               4500589