(IUCr) Crystallography Journals Online checkcif report

[Contents scheme]

Acta Cryst. (2005). E61, o1085-o1086 [ doi:10.1107/S1600536805008469 ]

(2R,3R)-Diacetyltartaric acid anhydride

Z.-B. Qi, M.-J. Zhang, D.-Y. Yuan, S.-S. Ma and X.-Q. Wang

Online 25 March 2005

Key indicators

Single-crystal X-ray study
T = 293 K
Mean (C-C) = 0.003 Å
R factor = 0.035
wR factor = 0.100
Data-to-parameter ratio = 10.0

checkCIF/PLATON results

No syntax errors found




Alert level B
PLAT432_ALERT_2_B Short Inter X...Y Contact  O7     ..  C4      ..       2.79 Ang.  

Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT199_ALERT_1_C Check the Reported cell_measurement_temperature         293       
PLAT200_ALERT_1_C Check the Reported cell_ambient_temperature ....        293       
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C7     
PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety         C6     
PLAT432_ALERT_2_C Short Inter X...Y Contact  O2     ..  C4      ..       2.95 Ang.  

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           27.91
           From the CIF: _reflns_number_total               1381
           Count of symmetry unique reflns         1381
           Completeness (_total/calc)            100.00%
           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
   1 ALERT level B = Potentially serious problem
   6 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

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