A Bond Flexibility Index Derived from the Constitution of Molecules
Claus‐Wilhelm von der Lieth, Klaus Stumpf-Nothof, Ursula Prior · Journal of Chemical Information and Computer Sciences · 1996
The concept of flexibility is a widely used qualitative term in chemistry. However, only a few attempts have been made to quantify this structural property. The basic assumptions used in a description of molecular flexibility are outlined, and their consequences are discussed. A local description is needed to handle molecules which exhibit both flexible and rigid parts. The assumption is made that local molecular flexibility can be described by defining structural features which exhibit an intrinsic flexibility which is largely independent of directly connected functional groups. A flexibility index which can be defined for each bond in a molecule is presented. It allows one to describe local differences between flexible and rigid regions within one molecule. Some potential applications of the bond flexibility index will be discussed.