Re: Any quantum chemists / physicists?

*To*: mathgroup at smc.vnet.net*Subject*: [mg30205] Re: Any quantum chemists / physicists?*From*: Gustavo Seabra <gseabra at swbell.net>*Date*: Thu, 2 Aug 2001 03:16:00 -0400 (EDT)*References*: <9k5r6g$hc1$1@smc.vnet.net> <9k88k4$52q$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Thanks. At least now I know what to do. Are there any books / web sites with useful information you could recommend? Gustavo. "Alan Mason" <amason2 at austin.rr.com> wrote in message news:9k88k4$52q$1 at smc.vnet.net... > Hello, > I am interested in computational quantum chemistry and have written > Mathematica code to handle differential operator calculus, commutators, etc. > I use it as a tool to spit out "exact" rotational-vibrational Hamiltonians > for simple molecules; see, e.g., the paper by Bramley et al., Molec. Phys., > Vol. 73 (1991), pp. 1183-1208. I also have some Mathematica code for > checking the calculations on pp. 419-423 of the book Quantum Field Theory by > Itzykson and Zuber; this code is the core of a QFT package that I'll > probably never write. By the way, I do not get their result. (In any case, > it was sheer madness on their part to include such a beastly calculation in > what is supposed to be a graduate text on QFT!!) > > There is information about differential operator calculus in the Mathematica > Archives, and you might want to search there. I don't know if any genuinely > useful full-blown commercial QFT package exists, even though Mathematica was > originally created to assist in just this field. Has anyone has ever used > such a package to answer a nontrivial QFT problem, such as computing the > Lamb shift through order 4 in alpha, say? Here I mean "used in a systematic > way with little or no human intervention" -- not just computing a whole > bunch of QFT integrals piecemeal. A few months ago I downloaded some code > from a web site that used to be linked to the Mathematica site, but I found > it to be buggy and not useful. > > It's difficult to write good general commercial packages that give useful > results for whole classes of significant problems. Any such package is > likely to be expensive, as it is hard to develop, it's specialized, and > there won't be many users. (Of course, Wolfram Research has already taken > care of integration and ordinary differential equations.) So it's probably > best to write your own code, tailored to your particular application. To > do this you'll need to thoroughly understand the pattern matcher, which will > take some study. I have found the effort very worthwhile. > "Gustavo Seabra" <gseabra at swbell.net> wrote in message > news:9k5r6g$hc1$1 at smc.vnet.net... > > Hello, > > > > Are there any quantum chemists / physicists around using Mathematica? > I > > was wondering if there is any package that handles things like > commutators, > > operators algebra, second quantization, superoperators, etc... > > > > Thanks, > > -- > > ----------------------------------------------------------------- > > Gustavo Seabra - Graduate Student > > Chemistry Department > > Kansas State University > > ----------------------------------------------------------------- > > > > > > >