(IUCr) Crystallography Journals Online checkcif report

[Contents scheme]

Acta Cryst. (2004). E60, o1437-o1438 [ doi:10.1107/S1600536804018021 ]

2,4-Dimethyl-1,5-diphenylpenta-1,4-dien-3-one

X.-R. Hu, J.-M. Gu and W.-M. Xu

Online 31 July 2004

Key indicators

Single-crystal X-ray study
T = 296 K
Mean (C-C) = 0.003 Å
R factor = 0.034
wR factor = 0.099
Data-to-parameter ratio = 7.0

checkCIF/PLATON results

No syntax errors found




Alert level C
REFNR01_ALERT_3_C  Ratio of reflections to parameters is < 8 for a
            non-centrosymmetric structure, where ZMAX < 18
            sine(theta)/lambda                0.6482
            Proportion of unique data used    0.7909
            Ratio reflections to parameters   7.0098
PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax .LT. 18) .....       7.01       

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.43
           From the CIF: _reflns_number_total                904
           Count of symmetry unique reflns          905
           Completeness (_total/calc)             99.89%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present           no

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion