Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Variables used to describe chain conformations. Force is applied in the 
direction. The arc length along the chain is s, and the vector r(s) = (x(s), y(s), z(s)) is the coordinate of the chain at arc length s. The vector 
is the unit vector tangent to the chain at s.
