(IUCr) Crystallography Journals Online checkcif report

[Contents scheme]

Acta Cryst. (2005). E61, o2724-o2726 [ doi:10.1107/S1600536805023822 ]

Isopropyl 2,5-anhydro-3,4-di-O-tert-butyldiphenylsilyl-L-ribonate

A. F. G. Glawar, D. J. Watkin, G. J. Sanjayan, G. E. Tranter, A. A. Edwards and G. W. J. Fleet

Online 27 July 2005

Key indicators

Single-crystal X-ray study
T = 190 K
Mean (C-C) = 0.003 Å
R factor = 0.050
wR factor = 0.096
Data-to-parameter ratio = 20.5

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT220_ALERT_2_A Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       6.37 Ratio 
PLAT220_ALERT_2_A Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       6.70 Ratio 
PLAT222_ALERT_3_A Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       8.19 Ratio 
PLAT222_ALERT_3_A Large Non-Solvent    H     Ueq(max)/Ueq(min) ...      10.00 Ratio 
PLAT242_ALERT_2_A Check Low       Ueq as Compared to Neighbors for        C28     
PLAT242_ALERT_2_A Check Low       Ueq as Compared to Neighbors for       C128     

Alert level B
ABSTM02_ALERT_3_B  The ratio of expected to reported Tmax/Tmin(RR') is < 0.75
            Tmin and Tmax reported:      0.700     0.970
            Tmin(prime) and Tmax expected:      0.946     0.973
            RR(prime) =      0.742
            Please check that your absorption correction is appropriate.
PLAT029_ALERT_3_B _diffrn_measured_fraction_theta_full Low .......       0.95       
PLAT061_ALERT_3_B Tmax/Tmin Range Test RR' too Large .............       0.74       
PLAT111_ALERT_2_B ADDSYM Detects (Pseudo) Centre of Symmetry .....         87 PerFit

Alert level C
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT213_ALERT_2_C Atom C29     has ADP max/min Ratio .............       3.20 prolat
PLAT213_ALERT_2_C Atom C130    has ADP max/min Ratio .............       3.50 prolat
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for        C40     
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for       C118     
PLAT390_ALERT_3_C Deviating Methyl C29     X-C-H Bond Angle ......     100.00 Deg.  
PLAT395_ALERT_2_C Deviating  X-O-Y  Angle from 120 Deg for      O2     140.60 Deg.  
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........         52       

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           30.01
           From the CIF: _reflns_number_total              17372
           Count of symmetry unique reflns        11468
           Completeness (_total/calc)            151.48%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      5904
           Fraction of Friedel pairs measured     0.515
           Are heavy atom types Z>Si present        yes

   6 ALERT level A = In general: serious problem
   4 ALERT level B = Potentially serious problem
   8 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
  10 ALERT type 2 Indicator that the structure model may be wrong or deficient
   6 ALERT type 3 Indicator that the structure quality may be low
   3 ALERT type 4 Improvement, methodology, query or suggestion