From: jack correia <jcorreia@fiona.umsmed.edu>
  To  : Julius.Clauwaert <clauwaer@uia.ua.ac.be>
  Date: Mon, 15 Dec 1997 10:04:09 -0600

Re: artractive molecules?

        What is the physical significance of a negative B?  It is well known
that a dimer K2 and B (a negative B?) compensate for each other creating a
difficult fitting problem.  (see Johnson et al, 1981 paper on Nonlin &
Stafford & Yphantis ?1972 paper on virial expansion; there is also a problem
in van Holde's book on this)  Thus a negative B is actually association.
We have seen cases where optical artifacts contribute to spurious B values,
but only if dc/dr excedes 15.0.  Heterogeneity of course also contributes to
inconsistent values.  Does MW vs c superimpose
---------------------------------------------
| Dr. Jack Correia                           | 
| Department of Biochemistry                 |
| University of Mississippi Medical Center   |
| 2500 North State Street                    |
| Jackson, MS 39216                          |  
| (601) 984-1522                             |
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| jcorreia@fiona.umsmed.edu                  |
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