Finding Force Field Parameters for Molecular Modeling | Sigma & Epsilon

AI Thread Summary
The discussion centers on the search for force field parameters, particularly Lennard-Jones parameters (sigma and epsilon), for nonbonded interactions between atoms in molecular modeling. Users express difficulty in finding these parameters online and share links to relevant resources, including academic papers and databases. The focus is on organic compounds primarily involving carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur. Participants mention the availability of AMBER force field parameters and express a desire for additional Lennard-Jones parameters, indicating a collaborative approach to sharing information and resources. Access issues with certain articles are noted, highlighting the challenges in obtaining specific data.
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I am looking for some force field parameters for nonbonded forces between atoms.

In most molecular modeling programs Lennard-Jones function is used to calculate Van der Waals forces where sigma and epsilon are constant values for a pair of atoms. But i cannot find them anywhere.


Or if anyone has complete force field parameters (bonded and nonbonded interactions) i would be more than happy to have it!
 
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... actually seems pretty difficult to find any online (if do some fitting etc expands a bit). What have come across & stored:

http://www3.interscience.wiley.com/cgi-bin/abstract/33880/ABSTRACT?CRETRY=1&SRETRY=0
http://arxiv.org/PS_cache/cond-mat/pdf/9805/9805048.pdf
http://www.biochemtech.uni-halle.de/PPS2/course/section7/os_non.html#lj

what atoms, solids, compounds ... , did you've in mind? I've a collection of papers about the topic where can seek some specific values.
 
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Thank you for your links!
The last one looks the most interesting to me.
I am interested in organic compound.. so mainly C H O N P S elements.

I can't access the article on wiley page though.
 
Weird ... I can't access that Wiley one myself anylonger :rolleyes: :smile: . I can PM/email you a couple of related reports etc. about LJ parameters have collected containing those elements if you need some more specific info (something have collected along the way for a basis of own work)?
 
Ok i found that AMBER force field parameters are avalible on their homepage: http://amber.scripps.edu/ and there is also a link to some other page where they have a nice file: http://www.chpc.utah.edu/~cheatham/cornell_all_prm

But anyway i would like more LJ parameters if you have.. see PM please.
 
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