data_2003243
_journal_name_full     'Acta Crystallographica'
_journal_year          1995
_journal_volume    	C51
_journal_page_first    	351
_journal_page_last    	353
_publ_section_title    	
;
Triclinic Mg~2~B~2~O~5~
;
_chemical_formula_sum    	'B2 Mg2 O5'
_chemical_formula_weight    	150.23
loop_
    _symmetry_equiv_pos_as_xyz
    'x,y,z'
    '-x,-y,-z'
_symmetry_space_group_name_H-M    	'P -1'
_cell_length_a    	6.149(3)
_cell_length_b    	9.221(8)
_cell_length_c    	3.121(1)
_cell_angle_alpha    	90.29(5)
_cell_angle_beta    	92.23(4)
_cell_angle_gamma    	104.30(5)
_cell_volume    	171.4(2)
_cell_formula_units_Z    	2
_exptl_crystal_density_diffrn    	2.91
_exptl_crystal_density_meas    	?
_diffrn_radiation_type    	'MoK\a'
_diffrn_radiation_wavelength    	0.71069
_cell_measurement_reflns_used    	20
_cell_measurement_theta_min    	10
_cell_measurement_theta_max    	25
_exptl_absorpt_coefficient_mu    	0.567
_cell_measurement_temperature    	296
_exptl_crystal_description    	'Rectangular'
_exptl_crystal_size_max    	0.3
_exptl_crystal_size_mid    	0.1
_exptl_crystal_size_min    	0.1
_exptl_crystal_size_rad    	?
_exptl_crystal_colour    	'White'
_chemical_compound_source    	?
_diffrn_measurement_device    	'Rigaku AFC5R'
_diffrn_measurement_method    	'\w-2\q'
_exptl_absorpt_correction_type    	'empirical'
_exptl_absorpt_correction_T_min    	0.711
_exptl_absorpt_correction_T_max    	1.00
_diffrn_reflns_number    	2276
_reflns_number_total    	2133
_reflns_number_observed    	1944
_reflns_observed_criterion    	I>3\s(I)
_diffrn_reflns_av_R_equivalents    	0.043
_diffrn_reflns_theta_max    	40
_diffrn_reflns_limit_h_min    	0
_diffrn_reflns_limit_h_max    	11
_diffrn_reflns_limit_k_min    	-17
_diffrn_reflns_limit_k_max    	17
_diffrn_reflns_limit_l_min    	-6
_diffrn_reflns_limit_l_max    	6
_diffrn_standards_number    	3
_diffrn_standards_interval_count    	250
_diffrn_standards_interval_time    	?
_diffrn_standards_decay_%    	-1.0
_refine_ls_structure_factor_coef    	F
_refine_ls_R_factor_obs    	0.030
_refine_ls_wR_factor_obs    	0.047
_refine_ls_goodness_of_fit_obs    	1.55
_refine_ls_number_reflns    	1944
_refine_ls_number_parameters    	82
_refine_ls_hydrogen_treatment    	?
_refine_ls_weighting_scheme    	'w=1/\s^2^(F)'
_refine_ls_shift/esd_max    	0.0008
_refine_diff_density_max    	0.37
_refine_diff_density_min    	-0.52
_refine_ls_extinction_method    	none
_refine_ls_extinction_coef    	?
_atom_type_scat_source    	'Cromer & Waber (1974)'
loop_
    _atom_site_label
    _atom_site_fract_x
    _atom_site_fract_y
    _atom_site_fract_z
    _atom_site_B_iso_or_equiv
    Mg(1) .62787(5) .39744(3) .26628(8) .434(8)
    Mg(2) .78956(5) .14432(3) -.23131(9) .488(8)
    O(1) .90678(9) .31943(6) .2782(2) .54(1)
    O(2) .30443(9) .44687(6) .2347(2) .46(1)
    O(3) 1.13818(9) .19985(6) -.0619(2) .60(1)
    O(4) .7247(1) .00497(6) -.7297(2) .57(1)
    O(5) .52277(9) .24165(6) -.2424(2) .48(1)
    B(1) 1.1204(1) .33098(8) .1655(2) .43(2)
    B(2) .6818(1) -.14330(8) -.8007(2) .44(2)