data_2003803 _journal_name_full 'Acta Crystallographica' _journal_year 1995 _journal_volume C51 _journal_page_first 1658 _journal_page_last 1661 _publ_section_title ; Dimethyl 2-Methylcubane-1,4-dicarboxylate and Dimethyl 2,3-Dimethylcubane-1,4-dicarboxylate ; _chemical_formula_sum 'C14 H16 O4' _chemical_formula_weight 248.27 _symmetry_cell_setting Triclinic loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, -y, -z' _symmetry_space_group_name_H-M 'P -1' _cell_length_a 6.5835(12) _cell_length_b 9.487(2) _cell_length_c 10.546(2) _cell_angle_alpha 74.10(2) _cell_angle_beta 83.81(2) _cell_angle_gamma 87.89(2) _cell_volume 629.8(2) _cell_formula_units_Z 2 _exptl_crystal_density_diffrn 1.309 _exptl_crystal_density_meas ? _exptl_crystal_density_method ? _diffrn_radiation_type MoK\a _diffrn_radiation_wavelength 0.71069 _cell_measurement_reflns_used 25 _cell_measurement_theta_min 9.5 _cell_measurement_theta_max 17.5 _exptl_absorpt_coefficient_mu 0.096 _cell_measurement_temperature 293(1) _exptl_crystal_description 'Thin Plate' _exptl_crystal_size_max 0.58 _exptl_crystal_size_mid 0.30 _exptl_crystal_size_min 0.15 _exptl_crystal_colour colourless _chemical_compound_source 'Cristiano & Tsanaktsidis' _diffrn_measurement_device 'Enraf-Nonius CAD-4MachS' _diffrn_measurement_method \w:2\q _exptl_absorpt_correction_type none _exptl_absorpt_correction_T_min ? _exptl_absorpt_correction_T_max ? _diffrn_reflns_number 3687 _reflns_number_total 2900 _reflns_number_observed 2281 _reflns_observed_criterion >2sigma(I) _diffrn_reflns_av_R_equivalents 0.0082 _diffrn_reflns_theta_max 27.47 _diffrn_reflns_limit_h_min -8 _diffrn_reflns_limit_h_max 8 _diffrn_reflns_limit_k_min -12 _diffrn_reflns_limit_k_max 12 _diffrn_reflns_limit_l_min -2 _diffrn_reflns_limit_l_max 13 _diffrn_standards_number 3 _diffrn_standards_interval_count ? _diffrn_standards_interval_time 160 _diffrn_standards_decay_% -17 _refine_ls_structure_factor_coef Fsqd _refine_ls_R_factor_obs 0.0439 _refine_ls_wR_factor_obs 0.1256 _refine_ls_wR_factor_all 0.1330 _refine_ls_goodness_of_fit_obs 1.144 _refine_ls_goodness_of_fit_all 1.064 _refine_ls_number_reflns 2900 _refine_ls_number_parameters 228 _refine_ls_hydrogen_treatment refall _refine_ls_weighting_scheme 'calc w=1/[\s^2^(Fo^2^)+(0.0756P)^2^+0.0854P] where P=(Fo^2^+2F~c~^2^)/3' _refine_ls_shift/esd_max -0.001 _refine_diff_density_max 0.341 _refine_diff_density_min -0.250 _refine_ls_extinction_method 'SHELXL93 (Sheldrick, 1993)' _refine_ls_extinction_coef 0.056(8) loop_ _atom_type_symbol _atom_type_description _atom_type_scat_source _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag 'C' 'C' 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 0.0033 0.0016 'H' 'H' 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 0.0000 0.0000 'O' 'O' 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' 0.0106 0.0060 loop_ _atom_site_label _atom_site_occupancy _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv O(1) 1 0.3157(2) 0.22326(11) 0.44545(10) 0.0515(3) O(2) 1 0.2600(2) 0.00199(13) 0.58404(12) 0.0696(4) O(3) 1 0.6704(2) 0.26555(10) 1.04285(10) 0.0469(3) O(4) 1 0.7304(2) 0.48621(11) 0.90249(11) 0.0541(3) C(1) 1 0.4180(2) 0.18423(13) 0.65602(13) 0.0357(3) C(2) 1 0.3297(2) 0.32056(13) 0.70355(12) 0.0334(3) C(3) 1 0.3622(2) 0.23338(13) 0.84971(12) 0.0336(3) C(4) 1 0.5833(2) 0.30103(13) 0.82844(12) 0.0333(3) C(5) 1 0.5503(2) 0.38515(14) 0.68333(12) 0.0350(3) C(6) 1 0.6377(2) 0.25132(15) 0.63494(14) 0.0385(3) C(7) 1 0.6706(2) 0.16545(14) 0.78056(13) 0.0382(3) C(8) 1 0.4512(2) 0.10028(14) 0.80099(13) 0.0371(3) C(9) 1 0.3234(2) 0.12367(14) 0.56140(13) 0.0391(3) C(10) 1 0.2223(4) 0.1791(2) 0.3455(2) 0.0603(5) C(11) 1 0.1411(2) 0.4046(2) 0.6606(2) 0.0458(4) C(12) 1 0.2097(2) 0.2229(2) 0.96750(15) 0.0462(4) C(13) 1 0.6699(2) 0.36389(13) 0.92480(12) 0.0342(3) C(14) 1 0.7393(3) 0.3161(2) 1.1480(2) 0.0503(4) H(5) 1 0.5871(22) 0.4882(17) 0.6409(15) 0.038(4) H(6) 1 0.7317(26) 0.2556(18) 0.5544(17) 0.051(4) H(7) 1 0.7958(26) 0.1114(17) 0.8080(15) 0.045(4) H(8) 1 0.4107(24) -0.0002(18) 0.8455(16) 0.045(4) H(10A) 1 0.0999(38) 0.1386(27) 0.3776(24) 0.092(8) H(10B) 1 0.2176(38) 0.2613(28) 0.2676(27) 0.097(8) H(10C) 1 0.3060(43) 0.1038(31) 0.3209(25) 0.103(8) H(11A) 1 0.1508(26) 0.4497(19) 0.5666(19) 0.060(5) H(11B) 1 0.0222(28) 0.3419(20) 0.6821(17) 0.062(5) H(11C) 1 0.1110(30) 0.4785(22) 0.7068(20) 0.072(6) H(12A) 1 0.2597(26) 0.1648(19) 1.0476(19) 0.059(5) H(12B) 1 0.0832(29) 0.1761(20) 0.9576(18) 0.065(5) H(12C) 1 0.1775(28) 0.3191(22) 0.9781(19) 0.069(6) H(14A) 1 0.8646(31) 0.3636(22) 1.1229(19) 0.067(6) H(14B) 1 0.6391(33) 0.3867(23) 1.1715(20) 0.072(6) H(14C) 1 0.7455(41) 0.2320(31) 1.2216(28) 0.105(8) loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_12 _atom_site_aniso_U_13 _atom_site_aniso_U_22 _atom_site_aniso_U_23 _atom_site_aniso_U_33 O(1) 0.0746(7) -0.0139(5) -0.0190(5) 0.0457(6) -0.0087(4) 0.0367(5) O(2) 0.1026(10) -0.0323(6) -0.0324(7) 0.0508(6) -0.0042(5) 0.0572(7) O(3) 0.0619(6) -0.0103(4) -0.0203(5) 0.0409(5) -0.0062(4) 0.0393(5) O(4) 0.0772(8) -0.0171(5) -0.0181(5) 0.0395(5) -0.0092(5) 0.0480(6) C(1) 0.0390(6) -0.0051(5) -0.0088(5) 0.0355(6) -0.0098(5) 0.0342(6) C(2) 0.0354(6) -0.0050(5) -0.0077(5) 0.0336(6) -0.0080(5) 0.0318(6) C(3) 0.0352(6) -0.0064(5) -0.0085(5) 0.0343(6) -0.0066(5) 0.0316(6) C(4) 0.0337(6) -0.0035(5) -0.0091(5) 0.0332(6) -0.0085(5) 0.0342(6) C(5) 0.0379(6) -0.0072(5) -0.0061(5) 0.0333(6) -0.0070(5) 0.0335(6) C(6) 0.0359(6) -0.0056(5) -0.0041(5) 0.0440(7) -0.0146(6) 0.0380(7) C(7) 0.0371(6) 0.0008(5) -0.0122(5) 0.0383(6) -0.0133(5) 0.0425(7) C(8) 0.0439(7) -0.0058(5) -0.0124(5) 0.0315(6) -0.0074(5) 0.0371(7) C(9) 0.0427(7) -0.0068(5) -0.0098(5) 0.0389(7) -0.0103(5) 0.0375(7) C(10) 0.0809(13) -0.0115(10) -0.0249(9) 0.0641(11) -0.0150(8) 0.0414(9) C(11) 0.0416(7) 0.0024(6) -0.0144(6) 0.0510(8) -0.0103(7) 0.0452(8) C(12) 0.0456(8) -0.0088(6) -0.0017(6) 0.0549(9) -0.0107(6) 0.0371(7) C(13) 0.0326(6) -0.0020(5) -0.0086(5) 0.0343(6) -0.0107(5) 0.0375(7) C(14) 0.0575(9) -0.0050(8) -0.0180(7) 0.0587(9) -0.0141(7) 0.0386(8)