Strong Axiality and Ising Exchange Interaction Suppress Zero-Field Tunneling of Magnetization of an Asymmetric Dy2 Single-Molecule Magnet
Yun-Nan Guo; Gong-Feng Xu; Wolfgang Wernsdorfer; Liviu Ungur; Yang Guo; Jinkui Tang; Hong-Jie Zhang; Liviu F. Chibotaru; Annie K. Powell; Journal of the American Chemical Society 133 (2011) 11948–11951; doi:10.1021/ja205035g

data_4106527
_publ_section_title
;
 Strong Axiality and Ising Exchange Interaction Suppress Zero-Field
 Tunneling of Magnetization of an Asymmetric Dy2 Single-Molecule Magnet
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              11948
_journal_page_last               11951
_journal_paper_doi               10.1021/ja205035g
_journal_volume                  133
_journal_year                    2011
_chemical_formula_sum            'C33 H37 Cl2 Dy2 N7 O9'
_chemical_formula_weight         1071.60
_chemical_name_systematic
; 
 ? 
;
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_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   9.6970(5)
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_cell_length_c                   13.9203(7)
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_cell_measurement_temperature    186(2)
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_cell_measurement_theta_min      2.27
_cell_volume                     3816.8(3)
_computing_cell_refinement       'Bruker SMART'
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_computing_data_reduction        'Bruker SMART'
_computing_molecular_graphics    'Bruker SHELXTL'
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_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      186(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega 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  0.0519
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_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       35
_diffrn_reflns_limit_k_min       -25
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_diffrn_reflns_limit_l_min       -17
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_diffrn_reflns_theta_max         26.04
_diffrn_reflns_theta_min         2.06
_diffrn_standards_decay_%        none
_diffrn_standards_number         none
_exptl_absorpt_coefficient_mu    4.086
_exptl_absorpt_correction_T_max  0.6398
_exptl_absorpt_correction_T_min  0.5434
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.865
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_exptl_crystal_F_000             2088
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_refine_diff_density_min         -0.693
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_refine_ls_extinction_method     none
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_refine_ls_matrix_type           full
_refine_ls_number_parameters     484
_refine_ls_number_reflns         7508
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.001
_refine_ls_R_factor_all          0.0618
_refine_ls_R_factor_gt           0.0352
_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^)+(0.0235P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0624
_refine_ls_wR_factor_ref         0.0705
_reflns_number_gt                5370
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_reflns_threshold_expression     >2sigma(I)
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