Electrostatic potential

I might have looked in the wrong places but I could find any info in the Guide and in the documents on the ChemAxon site on how the electrostatic potential in Marvin Space is calculated, or technical literature references to this effect. Any help would be appreciated.





Thanks.

Hi,





I am afraid that there is no detailed documentation on this topic and the reason behind is not just us being lazy.





The present EP model is rather simple minded and its main purpose is to demonstrate the surface coloring and property mapping in MarvinSpace. This is becasuse MarvinSpace - in its present shape - is 'just' a viewer, rather than a modelling tool.





The current method calculates the partial atomic charges based on the estimated orbital electronegativity, details of this method is discribed here:


http://www.chemaxon.com/marvin/chemaxon/marvin/help/Charge.html.


These charges are placed in atom centres and the electric potential is calculated as the sum of the point charges' individual potentials.





In the long term we would like to extend MarvinSpace with more and more modelling capabilities. In the next release Charmm EP will be supported, see the corresponding forum topic: http://www.chemaxon.com/forum/viewpost7906.html&sid=03cfc916c838b27dd07d0f18c0155ae5#7906


An example image of charmm EP colored surface is here: http://www.chemaxon.com/marvinspace/gallery/phi80.png





If you have any preference for a standard EP method please send us references and we will tell you if we can implement it.





Hope this helps,


Regards,


Miklos