(IUCr) Crystallography Journals Online checkcif report

[Contents scheme]

Acta Cryst. (2008). E64, o1562 [ doi:10.1107/S1600536808022381 ]

A polymorph of terephthalaldehyde

L. Teng and Z. Wang

Online 23 July 2008

Key indicators

Single-crystal X-ray study
T = 295 K
Mean (C-C) = 0.005 Å
R factor = 0.043
wR factor = 0.113
Data-to-parameter ratio = 7.2

checkCIF/PLATON results

No syntax errors found




Alert level C
PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax .LT. 18) .....       7.18      
PLAT340_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...          5      

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           25.50
           From the CIF: _reflns_number_total                653
           Count of symmetry unique reflns          655
           Completeness (_total/calc)             99.69%
           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
   0 ALERT type 5 Informative message, check