(IUCr) Crystallography Journals Online checkcif report

[Contents scheme]

Acta Cryst. (2004). E60, o907-o908 [ doi:10.1107/S1600536804009870 ]

(1R,2R)-1,3-Bis(tert-butyldimethylsilyloxy)-2-(4-hydroxybutanamido)-1-(4-nitrophenyl)propane

D. Johansson, F. B. Larsen, A. D. Bond and P. Nielsen

Online 30 April 2004

Key indicators

Single-crystal X-ray study
T = 180 K
Mean (C-C) = 0.012 Å
R factor = 0.056
wR factor = 0.148
Data-to-parameter ratio = 6.3

checkCIF/PLATON results

No syntax errors found



Alert level A
THETM01_ALERT_3_A  The value of sine(theta_max)/wavelength is less than 0.550
            Calculated sin(theta_max)/wavelength =    0.5276

Author Response: Diffraction was relatively weak and data were truncated at 0.95 \%A.

PLAT023_ALERT_3_A Resolution (too) Low [sin(th)/Lambda < 0.6].....      22.02 Deg.  
PLAT027_ALERT_3_A _diffrn_reflns_theta_full (too) Low ............      22.02 Deg.  
PLAT220_ALERT_2_A Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       5.68 Ratio 
PLAT222_ALERT_3_A Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       7.22 Ratio 
PLAT242_ALERT_2_A Check Low    U(eq) as Compared to Neighbors ....       Si2A     

Alert level B
PLAT201_ALERT_2_B Isotropic non-H Atoms in Main Residue(s) .......          6       
PLAT222_ALERT_3_B Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       4.03 Ratio 
PLAT242_ALERT_2_B Check Low    U(eq) as Compared to Neighbors ....       C17A     
PLAT340_ALERT_3_B Low Bond Precision on C-C bonds (x 1000) Ang ...         12       
PLAT415_ALERT_2_B Short Inter D-H..H-X       H6OA   ..  H3B'    ..       1.91 Ang.  
PLAT417_ALERT_2_B Short Inter D-H..H-D       H6OA   ..  HN2B    ..       1.56 Ang.  

Alert level C
REFNR01_ALERT_3_C  Ratio of reflections to parameters is < 8 for a
            non-centrosymmetric structure, where ZMAX < 18
            sine(theta)/lambda                0.5276
            Proportion of unique data used    1.0000
            Ratio reflections to parameters   6.2559
PLAT089_ALERT_3_C Poor Data / Parameter Ratio (Zmax .LT. 18) .....       6.26       
PLAT213_ALERT_2_C Atom C19A    has ADP max/min Ratio .............       3.10 prolat
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       3.15 Ratio 
PLAT242_ALERT_2_C Check Low    U(eq) as Compared to Neighbors ....       C23A     
PLAT242_ALERT_2_C Check Low    U(eq) as Compared to Neighbors ....       C17'     
PLAT242_ALERT_2_C Check Low    U(eq) as Compared to Neighbors ....       Si1B     
PLAT242_ALERT_2_C Check Low    U(eq) as Compared to Neighbors ....       C17B     
PLAT301_ALERT_3_C Main Residue  Disorder .........................       9.00 Perc. 
PLAT413_ALERT_2_C Short Inter XH3 .. XHn     H11D   ..  H12D    ..       2.13 Ang.  
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........         12       

Alert level G
REFLT03_ALERT_4_G  WARNING: Large fraction of Friedel related reflns may
                     be needed to determine absolute structure
           From the CIF: _diffrn_reflns_theta_max           22.02
           From the CIF: _reflns_number_total               3985
           Count of symmetry unique reflns         4011
           Completeness (_total/calc)             99.35%
           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          yes

   6 ALERT level A = In general: serious problem
   6 ALERT level B = Potentially serious problem
  11 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
  13 ALERT type 2 Indicator that the structure model may be wrong or deficient
   9 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion