Questions for the MUD

[Charaf Benarafa <benarafa@RVC.ac.uk>]

Dear all,

I have a few questions for Mud session later on and as I am not a rapid
type-writer I prefer to send my questions first by email...

1) How do we know which are the 4 atoms involved in a torsion angle, is
there a chemical rule or is it something conventional for important angles
like Phi, Psi, Omega and chi1? How do you decide for other Chi angles?

2) Having decided the which atoms are involved in a torsion, are angles of
torsion always positive when looked clockwise and negative a when going
anticlokwise?

3) About chi angles at
http://pps9900.cryst.bbk.ac.uk/ppscore/section3/jonc/conform.html
The diagram says chi1 gauche(+) makes a -60 angle, should we read +60?

See you soon in the MUD.

Charaf






Charaf Benarafa
DVM, PhD student
Department of Pathology and Infectious Diseases
The Royal Veterinary College
Hawkshead Lane, North Mymms
Hatfield, Herts AL9 7TA
tel. 01707 666 295
benarafa@rvc.ac.uk