(IUCr) Crystallography Journals Online checkcif report

[Contents scheme]

Acta Cryst. (2005). E61, o2213-o2215 [ doi:10.1107/S1600536805018994 ]

3,4-Dihydroxy-9H-xanthen-9-one trihydrate

L. Gales, M. E. Sousa, M. M. M. Pinto and A. M. Damas

Online 24 June 2005

Key indicators

Single-crystal X-ray study
T = 291 K
Mean (C-C) = 0.004 Å
R factor = 0.050
wR factor = 0.151
Data-to-parameter ratio = 8.8

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT027_ALERT_3_A _diffrn_reflns_theta_full (too) Low ............      24.20 Deg.

Author Response: The crystals were very thin plates which did not diffract very well and therefore reflections could only be measured up to \Qmax=24.20\%.

PLAT029_ALERT_3_A _diffrn_measured_fraction_theta_full Low .......       0.93

Author Response: The crystals were very thin plates which did not diffract very well and therefore reflections could only be measured up to \Qmax=24.20\%.


Alert level C
REFLT03_ALERT_3_C  Reflection count < 95% complete
           From the CIF: _diffrn_reflns_theta_max           24.20
           From the CIF: _diffrn_reflns_theta_full          24.20
           From the CIF: _reflns_number_total               1882
           TEST2: Reflns within _diffrn_reflns_theta_max
           Count of symmetry unique reflns         2032
           Completeness (_total/calc)             92.62%
REFNR01_ALERT_3_C  Ratio of reflections to parameters is < 10 for a
            centrosymmetric structure
            sine(theta)/lambda                0.5768
            Proportion of unique data used    1.0000
            Ratio reflections to parameters   8.8357
THETM01_ALERT_3_C  The value of sine(theta_max)/wavelength is less than 0.590
            Calculated sin(theta_max)/wavelength =    0.5768
PLAT022_ALERT_3_C Ratio Unique / Expected Reflections too Low ....       0.93       
PLAT023_ALERT_3_C Resolution (too) Low [sin(th)/Lambda < 0.6].....      24.20 Deg.  
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT088_ALERT_3_C Poor Data / Parameter Ratio ....................       8.84       
PLAT480_ALERT_4_C Long H...A H-Bond Reported H22W   ..  O4      ..       2.66 Ang.  
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          2       
              H2 O                                                              
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          3       
              H2 O                                                              
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          4       
              H2 O                                                              

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

   1 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
   8 ALERT type 3 Indicator that the structure quality may be low
   4 ALERT type 4 Improvement, methodology, query or suggestion