CCL: total energy : adf

[marcel.swart .. icrea.es]

 Sent to CCL by: marcel.swart^^icrea.es
 Dear Shrinwantu,
 the total bonding energy in ADF is calculated relative to atomic or
 molecular fragments; more information can be found in the
 "Chemistry with ADF" paper that appeared in J.Comput.Chem.
 in 2001: JCC 2001, 22, 931-967.
 Given in the ADF output is (apart from the Bonding Energy that can
 be decomposed into physical components like Pauli Repulsion, Electrostatics,
 and Orbital Interactions) also the total energy of the fragments,
 which is given as "Total XC:". However, the total energy is generally
 not necessary when you always use the same atomic fragments.
 The interaction energy can of course be corrected for BSSE, although
 with the Slater-type orbitals, these corrections are usually much smaller
 than with GTO's (ca. 0.5-1.0 kcal/mol using TZ2P basis sets). Again,
 see the "Chemistry with ADF" paper.
 NB.
 I don't understand what you mean with "there is a problem..",
 as far as I can see there is no problem; for more details, visit
 the SCM website, look for the Forum, and the JCC paper mentioned
 above.
 If you still have questions, please send a mail to support,,scm.com.
 Quoting "Shrinwantu Pal paul**jncasr.ac.in"
 <owner-chemistry,,ccl.net>:
> I DO NOT SEEM TO FIGURE OUT HOW TO USE ADF IN FINDING
>  OUT THE TOTAL
>  ENERGY OF A SYSTEM.
> I WOULD LIKE TO STRESS THAT I HAVE USED ADF TO GET INTERACTION
>  ENERGIES BETWEEN FRAGMENTS, BUT AS IN THIS CASE I NEED THE TOTAL
>  ENERGY.
> IS THERE A WAY WHERE ONE CAN DEFINE EACH ATOM AS A FRAGMENT AND
>  CALCULATE INTERACTION ENERGY?
> BUT THEN THERE IS A PROBLEM ABOUT THE ATOM NOT BEING CONSIDERED
>  PROPERLY AS THE ATOM WHILE IN BONDING, IS NO LONGER SPHERICAL.
>  DO WE THEN CORRECT THE INTERACTION ENERGY SUPPORTED BY 'BSSE' ?
>  ANY HELP FROM YOU ALL WOULD BE HUMBLY APPRECIATED.
>  ~Shrinwantu Pal
>  TSU
>  JNCASR
>  INDIA