data_2005src1568
 
_audit_creation_method            SHELXL-97
_chemical_name_systematic
;
 ?
;
_chemical_name_common             ?
_chemical_melting_point           ?
_chemical_formula_moiety          'C24 H32 O'
_chemical_formula_sum
 'C24 H32 O'
_chemical_formula_weight          336.50
 
loop_
 _atom_type_symbol
 _atom_type_description
 _atom_type_scat_dispersion_real
 _atom_type_scat_dispersion_imag
 _atom_type_scat_source
 'C'  'C'   0.0033   0.0016
 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
 'H'  'H'   0.0000   0.0000
 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
 'O'  'O'   0.0106   0.0060
 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
 
_symmetry_cell_setting            Monoclinic
_symmetry_space_group_name_H-M    P2(1)/c
_symmetry_space_group_name_hall   '-P 2ybc'
 
loop_
 _symmetry_equiv_pos_as_xyz
 'x, y, z'
 '-x, y+1/2, -z+1/2'
 '-x, -y, -z'
 'x, -y-1/2, z-1/2'
 
_cell_length_a                    11.5027(3)
_cell_length_b                    13.7029(2)
_cell_length_c                    27.1787(7)
_cell_angle_alpha                 90.00
_cell_angle_beta                  101.0000(10)
_cell_angle_gamma                 90.00
_cell_volume                      4205.21(17)
_cell_formula_units_Z             8
_cell_measurement_temperature     120(2)
_cell_measurement_reflns_used     9805
_cell_measurement_theta_min       2.91
_cell_measurement_theta_max       27.48
 
_exptl_crystal_description        block
_exptl_crystal_colour             colourless
_exptl_crystal_size_max           0.40
_exptl_crystal_size_mid           0.40
_exptl_crystal_size_min           0.30
_exptl_crystal_density_meas       ?
_exptl_crystal_density_diffrn     1.063
_exptl_crystal_density_method     'not measured'
_exptl_crystal_F_000              1472
_exptl_absorpt_coefficient_mu     0.062
_exptl_absorpt_correction_type    multi-scan
_exptl_absorpt_correction_T_min   0.9754
_exptl_absorpt_correction_T_max   0.9815
_exptl_absorpt_process_details    'SADABS V2.10 (Sheldrick, G.M., 2003)'
 
_exptl_special_details
;
 ?
;
 
_diffrn_ambient_temperature       120(2)
_diffrn_radiation_wavelength      0.71073
_diffrn_radiation_type            MoK\a
_diffrn_radiation_source          'Bruker-Nonius FR591 rotating anode'
_diffrn_radiation_monochromator   graphite
_diffrn_measurement_device_type   'Bruker-Nonius KappaCCD Area Detector'
_diffrn_measurement_method        'φ and ω scans'
_diffrn_detector_area_resol_mean  9.091
_diffrn_standards_number          none
_diffrn_standards_interval_count  ?
_diffrn_standards_interval_time   ?
_diffrn_standards_decay_%         negligible
_diffrn_reflns_number             52713
_diffrn_reflns_av_R_equivalents   0.0662
_diffrn_reflns_av_sigmaI/netI     0.0633
_diffrn_reflns_limit_h_min        -14
_diffrn_reflns_limit_h_max        14
_diffrn_reflns_limit_k_min        -17
_diffrn_reflns_limit_k_max        17
_diffrn_reflns_limit_l_min        -33
_diffrn_reflns_limit_l_max        35
_diffrn_reflns_theta_min          2.97
_diffrn_reflns_theta_max          27.50
_reflns_number_total              9622
_reflns_number_gt                 5959
_reflns_threshold_expression      >2sigma(I)
 
_computing_data_collection        ?
_computing_cell_refinement        'DENZO, COLLECT'
_computing_data_reduction         'DENZO, COLLECT'
_computing_structure_solution     'SHELXS-97 (Sheldrick, 1997)'
_computing_structure_refinement   'SHELXL-97 (Sheldrick, 1997)'
_computing_molecular_graphics     'PLATON (Spek, 1990)'
_computing_publication_material   ?
 
_refine_special_details
;
 Refinement of F² against ALL reflections.  The weighted R-factor wR and
 goodness of fit S are based on F², conventional R-factors R are based
 on F, with F set to zero for negative F². The threshold expression of
 F² > 2sigma(F²) is used only for calculating R-factors(gt) etc. and is
 not relevant to the choice of reflections for refinement.  R-factors based
 on F² are statistically about twice as large as those based on F, and R-
 factors based on ALL data will be even larger.
;
 
_refine_ls_structure_factor_coef  Fsqd
_refine_ls_matrix_type            full
_refine_ls_weighting_scheme       calc
_refine_ls_weighting_details
 'calc w=1/[σ²(Fo²)+(0.0582P)²+0.8350P] where P=(Fo²+2Fc²)/3'
_atom_sites_solution_primary      direct
_atom_sites_solution_secondary    difmap
_atom_sites_solution_hydrogens    geom
_refine_ls_hydrogen_treatment     constr
_refine_ls_extinction_method      none
_refine_ls_extinction_coef        ?
_refine_ls_number_reflns          9622
_refine_ls_number_parameters      463
_refine_ls_number_restraints      0
_refine_ls_R_factor_all           0.1035
_refine_ls_R_factor_gt            0.0515
_refine_ls_wR_factor_ref          0.1335
_refine_ls_wR_factor_gt           0.1109
_refine_ls_goodness_of_fit_ref    1.016
_refine_ls_restrained_S_all       1.016
_refine_ls_shift/su_max           0.011
_refine_ls_shift/su_mean          0.000
 
loop_
 _atom_site_label
 _atom_site_type_symbol
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_U_iso_or_equiv
 _atom_site_adp_type
 _atom_site_occupancy
 _atom_site_symmetry_multiplicity
 _atom_site_calc_flag
 _atom_site_refinement_flags
 _atom_site_disorder_assembly
 _atom_site_disorder_group
C1 C 0.52413(13) 0.77822(10) 0.03410(6) 0.0222(3) Uani 1 1 d . . .
H1 H 0.5744 0.7689 0.0681 0.027 Uiso 1 1 calc R . .
C2 C 0.39445(13) 0.77204(10) 0.03804(6) 0.0220(3) Uani 1 1 d . . .
C3 C 0.30748(14) 0.79066(11) -0.00403(6) 0.0280(4) Uani 1 1 d . . .
H3 H 0.3299 0.8100 -0.0345 0.034 Uiso 1 1 calc R . .
C4 C 0.18832(14) 0.78133(12) -0.00197(7) 0.0321(4) Uani 1 1 d . . .
H4 H 0.1296 0.7941 -0.0309 0.039 Uiso 1 1 calc R . .
C5 C 0.15552(14) 0.75346(12) 0.04218(7) 0.0328(4) Uani 1 1 d . . .
H5 H 0.0741 0.7460 0.0435 0.039 Uiso 1 1 calc R . .
C6 C 0.24073(15) 0.73641(12) 0.08435(7) 0.0317(4) Uani 1 1 d . . .
H6 H 0.2178 0.7186 0.1149 0.038 Uiso 1 1 calc R . .
C7 C 0.36026(14) 0.74521(11) 0.08226(6) 0.0266(4) Uani 1 1 d . . .
H7 H 0.4186 0.7327 0.1113 0.032 Uiso 1 1 calc R . .
C8 C 0.55359(13) 0.69978(11) -0.00095(6) 0.0249(4) Uani 1 1 d . . .
H8A H 0.5051 0.7115 -0.0346 0.030 Uiso 1 1 calc R . .
H8B H 0.5292 0.6360 0.0108 0.030 Uiso 1 1 calc R . .
C9 C 0.68427(13) 0.69205(11) -0.00634(6) 0.0228(3) Uani 1 1 d . . .
H9 H 0.7083 0.7590 -0.0151 0.027 Uiso 1 1 calc R . .
C10 C 0.69268(13) 0.62587(11) -0.05246(6) 0.0258(4) Uani 1 1 d . . .
H10 H 0.6440 0.5663 -0.0500 0.031 Uiso 1 1 calc R . .
C11 C 0.63728(15) 0.67860(12) -0.09948(7) 0.0322(4) Uani 1 1 d . . .
H11 H 0.6745 0.7373 -0.1068 0.039 Uiso 1 1 calc R . .
C12 C 0.54193(17) 0.65150(15) -0.13173(7) 0.0461(5) Uani 1 1 d . . .
H12A H 0.5015 0.5933 -0.1261 0.055 Uiso 1 1 calc R . .
H12B H 0.5138 0.6902 -0.1605 0.055 Uiso 1 1 calc R . .
C13 C 0.81978(14) 0.59145(12) -0.05426(7) 0.0311(4) Uani 1 1 d . . .
H13 H 0.8515 0.5577 -0.0218 0.037 Uiso 1 1 calc R . .
C14 C 0.81801(16) 0.51697(13) -0.09639(8) 0.0429(5) Uani 1 1 d . . .
H14A H 0.7942 0.5494 -0.1289 0.064 Uiso 1 1 calc R . .
H14B H 0.7615 0.4649 -0.0932 0.064 Uiso 1 1 calc R . .
H14C H 0.8972 0.4889 -0.0940 0.064 Uiso 1 1 calc R . .
C15 C 0.90457(16) 0.67416(14) -0.06005(8) 0.0423(5) Uani 1 1 d . . .
H15A H 0.9844 0.6478 -0.0583 0.063 Uiso 1 1 calc R . .
H15B H 0.9055 0.7217 -0.0330 0.063 Uiso 1 1 calc R . .
H15C H 0.8783 0.7062 -0.0925 0.063 Uiso 1 1 calc R . .
C16 C 0.76600(13) 0.66529(11) 0.04308(6) 0.0237(3) Uani 1 1 d . . .
C17 C 0.76718(14) 0.57209(11) 0.06540(7) 0.0303(4) Uani 1 1 d . . .
C18 C 0.69163(17) 0.48699(12) 0.04217(8) 0.0421(5) Uani 1 1 d . . .
H18A H 0.7225 0.4621 0.0134 0.063 Uiso 1 1 calc R . .
H18B H 0.6097 0.5089 0.0310 0.063 Uiso 1 1 calc R . .
H18C H 0.6939 0.4350 0.0671 0.063 Uiso 1 1 calc R . .
C19 C 0.84290(15) 0.55433(13) 0.11091(7) 0.0361(4) Uani 1 1 d . . .
H19 H 0.8419 0.4915 0.1257 0.043 Uiso 1 1 calc R . .
C20 C 0.91960(15) 0.62411(13) 0.13566(7) 0.0354(4) Uani 1 1 d . . .
C21 C 0.99997(18) 0.60313(16) 0.18537(7) 0.0539(6) Uani 1 1 d . . .
H21A H 0.9575 0.6163 0.2127 0.081 Uiso 1 1 calc R . .
H21B H 1.0702 0.6450 0.1891 0.081 Uiso 1 1 calc R . .
H21C H 1.0243 0.5345 0.1865 0.081 Uiso 1 1 calc R . .
C22 C 0.91841(14) 0.71480(12) 0.11343(6) 0.0297(4) Uani 1 1 d . . .
H22 H 0.9711 0.7636 0.1294 0.036 Uiso 1 1 calc R . .
C23 C 0.84272(13) 0.73731(11) 0.06852(6) 0.0245(4) Uani 1 1 d . . .
C24 C 0.84570(14) 0.84104(11) 0.04961(7) 0.0313(4) Uani 1 1 d . . .
H24A H 0.9037 0.8790 0.0731 0.047 Uiso 1 1 calc R . .
H24B H 0.7672 0.8706 0.0469 0.047 Uiso 1 1 calc R . .
H24C H 0.8682 0.8407 0.0166 0.047 Uiso 1 1 calc R . .
C25 C 0.52864(13) 0.95176(11) -0.11955(6) 0.0236(3) Uani 1 1 d . . .
H25 H 0.5003 0.8864 -0.1332 0.028 Uiso 1 1 calc R . .
C26 C 0.66301(14) 0.95249(10) -0.11020(6) 0.0246(4) Uani 1 1 d . . .
C27 C 0.72045(15) 0.91577(11) -0.14697(7) 0.0323(4) Uani 1 1 d . . .
H27 H 0.6748 0.8891 -0.1768 0.039 Uiso 1 1 calc R . .
C28 C 0.84287(16) 0.91735(12) -0.14099(8) 0.0387(5) Uani 1 1 d . . .
H28 H 0.8806 0.8921 -0.1665 0.046 Uiso 1 1 calc R . .
C29 C 0.90964(15) 0.95601(12) -0.09766(8) 0.0385(5) Uani 1 1 d . . .
H29 H 0.9936 0.9573 -0.0932 0.046 Uiso 1 1 calc R . .
C30 C 0.85418(15) 0.99266(12) -0.06093(7) 0.0365(4) Uani 1 1 d . . .
H30 H 0.9001 1.0195 -0.0312 0.044 Uiso 1 1 calc R . .
C31 C 0.73100(14) 0.99066(11) -0.06706(7) 0.0293(4) Uani 1 1 d . . .
H31 H 0.6936 1.0157 -0.0414 0.035 Uiso 1 1 calc R . .
C32 C 0.47818(13) 1.02936(11) -0.15773(6) 0.0258(4) Uani 1 1 d . . .
H32A H 0.5243 1.0284 -0.1850 0.031 Uiso 1 1 calc R . .
H32B H 0.4909 1.0939 -0.1412 0.031 Uiso 1 1 calc R . .
C33 C 0.34570(13) 1.02017(11) -0.18158(6) 0.0248(4) Uani 1 1 d . . .
H33 H 0.3016 1.0206 -0.1532 0.030 Uiso 1 1 calc R . .
C34 C 0.30553(13) 1.11301(11) -0.21323(6) 0.0252(4) Uani 1 1 d . . .
H34 H 0.3655 1.1256 -0.2347 0.030 Uiso 1 1 calc R . .
C35 C 0.18341(14) 1.10238(12) -0.24858(6) 0.0317(4) Uani 1 1 d . . .
H35 H 0.1861 1.0417 -0.2688 0.038 Uiso 1 1 calc R . .
C36 C 0.08135(16) 1.09133(15) -0.22049(8) 0.0459(5) Uani 1 1 d . . .
H36A H 0.0966 1.0355 -0.1976 0.069 Uiso 1 1 calc R . .
H36B H 0.0074 1.0806 -0.2446 0.069 Uiso 1 1 calc R . .
H36C H 0.0744 1.1508 -0.2012 0.069 Uiso 1 1 calc R . .
C37 C 0.15911(18) 1.18750(14) -0.28518(7) 0.0455(5) Uani 1 1 d . . .
H37A H 0.1505 1.2477 -0.2667 0.068 Uiso 1 1 calc R . .
H37B H 0.0860 1.1751 -0.3094 0.068 Uiso 1 1 calc R . .
H37C H 0.2252 1.1945 -0.3029 0.068 Uiso 1 1 calc R . .
C38 C 0.30662(14) 1.19948(12) -0.17916(7) 0.0306(4) Uani 1 1 d . . .
H38 H 0.2718 1.1911 -0.1504 0.037 Uiso 1 1 calc R . .
C39 C 0.35157(16) 1.28578(13) -0.18561(8) 0.0419(5) Uani 1 1 d . . .
H39A H 0.3873 1.2974 -0.2138 0.050 Uiso 1 1 calc R . .
H39B H 0.3483 1.3364 -0.1620 0.050 Uiso 1 1 calc R . .
C40 C 0.31944(13) 0.92149(11) -0.20793(6) 0.0243(4) Uani 1 1 d . . .
C41 C 0.35985(13) 0.89636(12) -0.25204(6) 0.0271(4) Uani 1 1 d . . .
C42 C 0.42441(15) 0.96601(12) -0.28095(7) 0.0334(4) Uani 1 1 d . . .
H42A H 0.4476 0.9314 -0.3091 0.050 Uiso 1 1 calc R . .
H42B H 0.4953 0.9911 -0.2587 0.050 Uiso 1 1 calc R . .
H42C H 0.3720 1.0205 -0.2937 0.050 Uiso 1 1 calc R . .
C43 C 0.33881(14) 0.80317(12) -0.27227(7) 0.0338(4) Uani 1 1 d . . .
H43 H 0.3679 0.7873 -0.3017 0.041 Uiso 1 1 calc R . .
C44 C 0.27714(15) 0.73268(12) -0.25117(8) 0.0375(4) Uani 1 1 d . . .
C45 C 0.25500(18) 0.63306(14) -0.27505(10) 0.0591(6) Uani 1 1 d . . .
H45A H 0.2714 0.5827 -0.2491 0.089 Uiso 1 1 calc R . .
H45B H 0.3071 0.6236 -0.2993 0.089 Uiso 1 1 calc R . .
H45C H 0.1722 0.6283 -0.2923 0.089 Uiso 1 1 calc R . .
C46 C 0.23733(15) 0.75783(12) -0.20803(7) 0.0361(4) Uani 1 1 d . . .
H46 H 0.1949 0.7108 -0.1928 0.043 Uiso 1 1 calc R . .
C47 C 0.25709(14) 0.84980(12) -0.18601(6) 0.0294(4) Uani 1 1 d . . .
C48 C 0.21060(17) 0.86810(14) -0.13832(7) 0.0421(5) Uani 1 1 d . . .
H48A H 0.1795 0.8071 -0.1271 0.063 Uiso 1 1 calc R . .
H48B H 0.1472 0.9169 -0.1447 0.063 Uiso 1 1 calc R . .
H48C H 0.2750 0.8922 -0.1122 0.063 Uiso 1 1 calc R . .
O1 O 0.55084(9) 0.87131(7) 0.01429(4) 0.0240(3) Uani 1 1 d . . .
H1A H 0.5384 0.9159 0.0338 0.036 Uiso 1 1 calc R . .
O2 O 0.48142(9) 0.96990(7) -0.07523(4) 0.0264(3) Uani 1 1 d . . .
H2 H 0.5082 0.9283 -0.0533 0.040 Uiso 1 1 calc R . .
 
 
_geom_special_details
;
 All esds (except the esd in the dihedral angle between two l.s. planes)
 are estimated using the full covariance matrix.  The cell esds are taken
 into account individually in the estimation of esds in distances, angles
 and torsion angles; correlations between esds in cell parameters are only
 used when they are defined by crystal symmetry.  An approximate (isotropic)
 treatment of cell esds is used for estimating esds involving l.s. planes.
;
 
loop_
 _geom_bond_atom_site_label_1
 _geom_bond_atom_site_label_2
 _geom_bond_distance
 _geom_bond_site_symmetry_2
 _geom_bond_publ_flag
C1 O1 1.4404(17) . ?
C1 C8 1.517(2) . ?
C1 C2 1.518(2) . ?
C2 C7 1.384(2) . ?
C2 C3 1.392(2) . ?
C3 C4 1.388(2) . ?
C4 C5 1.379(2) . ?
C5 C6 1.378(2) . ?
C6 C7 1.392(2) . ?
C8 C9 1.541(2) . ?
C9 C16 1.530(2) . ?
C9 C10 1.565(2) . ?
C10 C11 1.500(2) . ?
C10 C13 1.546(2) . ?
C11 C12 1.320(2) . ?
C13 C15 1.523(2) . ?
C13 C14 1.531(2) . ?
C16 C17 1.413(2) . ?
C16 C23 1.414(2) . ?
C17 C19 1.392(2) . ?
C17 C18 1.518(2) . ?
C19 C20 1.385(3) . ?
C20 C22 1.381(2) . ?
C20 C21 1.512(2) . ?
C22 C23 1.392(2) . ?
C23 C24 1.514(2) . ?
C25 O2 1.4345(18) . ?
C25 C26 1.518(2) . ?
C25 C32 1.521(2) . ?
C26 C31 1.382(2) . ?
C26 C27 1.393(2) . ?
C27 C28 1.387(2) . ?
C28 C29 1.383(3) . ?
C29 C30 1.378(3) . ?
C30 C31 1.395(2) . ?
C32 C33 1.543(2) . ?
C33 C40 1.533(2) . ?
C33 C34 1.556(2) . ?
C34 C38 1.502(2) . ?
C34 C35 1.550(2) . ?
C35 C37 1.524(2) . ?
C35 C36 1.525(2) . ?
C38 C39 1.316(2) . ?
C40 C41 1.409(2) . ?
C40 C47 1.413(2) . ?
C41 C43 1.393(2) . ?
C41 C42 1.517(2) . ?
C43 C44 1.386(3) . ?
C44 C46 1.381(3) . ?
C44 C45 1.512(2) . ?
C46 C47 1.395(2) . ?
C47 C48 1.514(2) . ?
 
loop_
 _geom_angle_atom_site_label_1
 _geom_angle_atom_site_label_2
 _geom_angle_atom_site_label_3
 _geom_angle
 _geom_angle_site_symmetry_1
 _geom_angle_site_symmetry_3
 _geom_angle_publ_flag
O1 C1 C8 107.68(12) . . ?
O1 C1 C2 111.00(11) . . ?
C8 C1 C2 110.18(12) . . ?
C7 C2 C3 118.91(14) . . ?
C7 C2 C1 121.48(14) . . ?
C3 C2 C1 119.58(14) . . ?
C4 C3 C2 120.70(16) . . ?
C5 C4 C3 119.78(16) . . ?
C6 C5 C4 120.09(15) . . ?
C5 C6 C7 120.17(16) . . ?
C2 C7 C6 120.34(16) . . ?
C1 C8 C9 116.55(12) . . ?
C16 C9 C8 112.35(13) . . ?
C16 C9 C10 116.28(12) . . ?
C8 C9 C10 109.04(12) . . ?
C11 C10 C13 111.76(14) . . ?
C11 C10 C9 108.78(12) . . ?
C13 C10 C9 113.92(13) . . ?
C12 C11 C10 126.46(17) . . ?
C15 C13 C14 109.65(14) . . ?
C15 C13 C10 113.86(14) . . ?
C14 C13 C10 110.44(14) . . ?
C17 C16 C23 117.85(15) . . ?
C17 C16 C9 123.20(14) . . ?
C23 C16 C9 118.93(13) . . ?
C19 C17 C16 119.53(15) . . ?
C19 C17 C18 116.54(15) . . ?
C16 C17 C18 123.92(15) . . ?
C20 C19 C17 122.92(16) . . ?
C22 C20 C19 117.16(16) . . ?
C22 C20 C21 121.03(18) . . ?
C19 C20 C21 121.79(17) . . ?
C20 C22 C23 122.38(16) . . ?
C22 C23 C16 120.12(15) . . ?
C22 C23 C24 117.05(14) . . ?
C16 C23 C24 122.82(14) . . ?
O2 C25 C26 113.27(13) . . ?
O2 C25 C32 107.18(12) . . ?
C26 C25 C32 110.70(12) . . ?
C31 C26 C27 118.44(15) . . ?
C31 C26 C25 122.53(14) . . ?
C27 C26 C25 119.00(14) . . ?
C28 C27 C26 121.36(17) . . ?
C29 C28 C27 119.50(17) . . ?
C30 C29 C28 119.87(16) . . ?
C29 C30 C31 120.42(17) . . ?
C26 C31 C30 120.41(16) . . ?
C25 C32 C33 116.57(13) . . ?
C40 C33 C32 111.04(12) . . ?
C40 C33 C34 116.85(13) . . ?
C32 C33 C34 109.32(12) . . ?
C38 C34 C35 110.86(12) . . ?
C38 C34 C33 109.72(13) . . ?
C35 C34 C33 113.85(13) . . ?
C37 C35 C36 109.87(15) . . ?
C37 C35 C34 111.37(14) . . ?
C36 C35 C34 113.10(14) . . ?
C39 C38 C34 125.74(17) . . ?
C41 C40 C47 117.73(14) . . ?
C41 C40 C33 123.06(14) . . ?
C47 C40 C33 119.13(14) . . ?
C43 C41 C40 119.95(15) . . ?
C43 C41 C42 115.94(15) . . ?
C40 C41 C42 124.09(14) . . ?
C44 C43 C41 122.67(16) . . ?
C46 C44 C43 117.14(16) . . ?
C46 C44 C45 122.25(17) . . ?
C43 C44 C45 120.62(18) . . ?
C44 C46 C47 122.43(16) . . ?
C46 C47 C40 120.09(16) . . ?
C46 C47 C48 117.48(15) . . ?
C40 C47 C48 122.43(15) . . ?
 
_diffrn_measured_fraction_theta_max    0.996
_diffrn_reflns_theta_full              27.50
_diffrn_measured_fraction_theta_full   0.996
_refine_diff_density_max    0.221
_refine_diff_density_min   -0.198
_refine_diff_density_rms    0.044
