The self-assembling zwitterionic form of <small>L</small>-phenylalanine at neutral pH
Mossou, Estelle; Teixeira, Susana C. M.; Mitchell, Edward P.; Mason, Sax A.; Adler-Abramovich, Lihi; Gazit, Ehud; Forsyth, V. Trevor; Acta Crystallographica Section C 70 (2014) 326–331; doi:10.1107/S2053229614002563

data_2019503
_publ_section_title
;
 The self-assembling zwitterionic form of <small>L</small>-phenylalanine
 at neutral pH
;
_journal_coeditor_code           SK3518
_journal_issue                   3
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              326
_journal_page_last               331
_journal_paper_doi               10.1107/S2053229614002563
_journal_volume                  70
_journal_year                    2014
_chemical_formula_moiety         'C9 H11 N O2'
_chemical_formula_sum            'C9 H11 N O2'
_chemical_formula_weight         165.19
_chemical_name_common            L-phenylalanine
_space_group_crystal_system      monoclinic
_space_group_IT_number           4
_space_group_name_Hall           'P 2yb'
_space_group_name_H-M_alt        'P 1 21 1'
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2013
_cell_angle_alpha                90
_cell_angle_beta                 90.120(4)
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   6.0010(5)
_cell_length_b                   30.8020(17)
_cell_length_c                   8.7980(4)
_cell_measurement_reflns_used    841
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      20
_cell_measurement_theta_min      1
_cell_volume                     1626.24(18)
_computing_cell_refinement       'XDS (Kabsch, 1993)'
_computing_data_collection       'MxCuBE (Gabadinho <i>et al.</i>, 2010)'
_computing_data_reduction        'XDS (Kabsch, 1993)'
_computing_molecular_graphics    'PLATON (Spek, 2003, 2009)'
_computing_publication_material  'publCIF (Westrip, 2010)'
_computing_structure_refinement  'SHELXL-2013 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.990
_diffrn_measured_fraction_theta_max 0.855
_diffrn_measurement_device_type  'MD2M mini'
_diffrn_measurement_method       'profile from \q /2\q scans'
_diffrn_radiation_type           synchrotron
_diffrn_radiation_wavelength     0.61995
_diffrn_reflns_av_R_equivalents  0.0642
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       47
_diffrn_reflns_limit_k_min       -47
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            45788
_diffrn_reflns_theta_full        27.7
_diffrn_reflns_theta_max         30.540
_diffrn_reflns_theta_min         2.019
_exptl_absorpt_coefficient_mu    0.096
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.349
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       polygon
_exptl_crystal_F_000             704
_exptl_crystal_size_max          0.200
_exptl_crystal_size_mid          0.100
_exptl_crystal_size_min          0.070
_refine_diff_density_max         0.913
_refine_diff_density_min         -0.751
_refine_ls_abs_structure_details
;
Flack x determined using 4805 quotients [(I+)-(I-)]/[(I+)+(I-)]
(Parsons and Flack (2004), Acta Cryst. A60, s61).
;
_refine_ls_abs_structure_Flack   0.0(4)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.149
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     389
_refine_ls_number_reflns         12740
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.149
_refine_ls_R_factor_all          0.0776
_refine_ls_R_factor_gt           0.0641
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0808P)^2^+1.0335P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1640
_refine_ls_wR_factor_ref         0.1696
_reflns_number_gt                10932
_reflns_number_total             12740
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            sk3518sup1.cif
_cod_data_source_block           I
_cod_original_cell_volume        1626.24(17)
_cod_database_code               2019503
_cod_database_fobs_code          2019503
_shelx_estimated_absorpt_t_min   0.981
_shelx_estimated_absorpt_t_max   0.993
_shelx_hkl_checksum              30735
_shelx_res_checksum              8798
_shelxl_version_number           .2013