(IUCr) Crystallography Journals Online checkcif report

[Contents scheme]

Acta Cryst. (2004). E60, o1391-o1393 [ doi:10.1107/S1600536804017696 ]

4,5-Diphenyl-1H-imidazole-1-acetic acid

S. Gao, H. Zhao, L.-H. Huo, J.-S. Gao, S. M. Zain and S. W. Ng

Online 24 July 2004

Key indicators

Single-crystal X-ray study
T = 295 K
Mean (C-C) = 0.007 Å
R factor = 0.075
wR factor = 0.244
Data-to-parameter ratio = 10.0

checkCIF/PLATON results

No syntax errors found




Alert level B
PLAT601_ALERT_2_B Structure Contains Solvent Accessible VOIDS of .     134.00 A   3  

Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.800     0.979
            Tmin' and Tmax expected:      0.965     0.979
            RR' =      0.829
            Please check that your absorption correction is appropriate.
DIFMX01_ALERT_2_C  The maximum difference density is > 0.1*ZMAX*0.75
            _refine_diff_density_max given =      0.720
            Test value =      0.600
DIFMX02_ALERT_1_C  The minimum difference density is > 0.1*ZMAX*0.75
            The relevant atom site should be identified.
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.83       
PLAT097_ALERT_2_C Maximum (Positive) Residual Density ............       0.72 e/A   3
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT242_ALERT_2_C Check Low    U(eq) as Compared to Neighbors  for         C1     
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          7       

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           27.50
           From the CIF: _reflns_number_total               1903
           Count of symmetry unique reflns         1912
           Completeness (_total/calc)             99.53%
           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
   8 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

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