checkCIF procedure

PLAT214

 The main axes values of the ADP(S) of the minor residue(s) are determined and  
 ordered: U1 < U2 < U3. The value of SQRT(U3/U1) main axis ADP ratio (Angstrom  
 Units) is tested for the main residue(s). Large values may indicate
 unresolved disorder. Oblate criterium: U3 - U2 < U2 - U1. Prolate otherwise.