Sarcosine and betaine crystals upon cooling: structural motifs unstable at high pressure become stable at low temperatures.
Kapustin, E. A.; Minkov, V. S.; Boldyreva, E. V.; Physical chemistry chemical physics : PCCP 17 (2015) 3534–3543; doi:10.1039/c4cp05094k

data_7219096
_publ_section_title
;
 Sarcosine and betaine crystals upon cooling: structural motifs unstable
 at high pressure become stable at low temperatures.
;
_journal_issue                   5
_journal_name_full               'Physical chemistry chemical physics : PCCP'
_journal_page_first              3534
_journal_page_last               3543
_journal_paper_doi               10.1039/c4cp05094k
_journal_volume                  17
_journal_year                    2015
_chemical_formula_moiety         'C3 H7 N O2'
_chemical_formula_sum            'C3 H7 N O2'
_chemical_formula_weight         89.10
_chemical_name_common            N-methylglycine
_chemical_name_systematic
; 
 2-(Methylamino)acetic acid  
;
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_audit_update_record
;
2014-05-20 deposited with the CCDC.
2014-12-16 downloaded from the CCDC.
;
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   6.8141(5)
_cell_length_b                   7.9189(8)
_cell_length_c                   8.5887(6)
_cell_measurement_reflns_used    5416
_cell_measurement_temperature    295(2)
_cell_measurement_theta_max      29.51
_cell_measurement_theta_min      2.57
_cell_volume                     463.45(7)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      295(2)
_diffrn_detector_area_resol_mean 6.67
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device       '2-circle goniometer'
_diffrn_measurement_device_type  'STOE IPDS 2'
_diffrn_measurement_method       'rotation method'
_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  0.0266
_diffrn_reflns_av_sigmaI/netI    0.0222
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            5047
_diffrn_reflns_theta_full        29.16
_diffrn_reflns_theta_max         29.16
_diffrn_reflns_theta_min         3.50
_exptl_absorpt_coefficient_mu    0.107
_exptl_absorpt_correction_T_max  0.9894
_exptl_absorpt_correction_T_min  0.9687
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details   'X-SHAPE, Stoe&Cie, 2003'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.277
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             192
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.22
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.137
_refine_diff_density_min         -0.201
_refine_diff_density_rms         0.054
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.4(14)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.049
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     62
_refine_ls_number_reflns         1246
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.049
_refine_ls_R_factor_all          0.0406
_refine_ls_R_factor_gt           0.0330
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0476P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0751
_refine_ls_wR_factor_ref         0.0777
_reflns_number_gt                1077
_reflns_number_total             1246
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c4cp05094k2.cif
_cod_data_source_block           Sarcosine-295
_cod_depositor_comments
'Adding full bibliography for 7219096--7219113.cif.'
_cod_database_code               7219096