Re: Any quantum chemists / physicists?
- To: mathgroup at smc.vnet.net
- Subject: [mg30177] Re: Any quantum chemists / physicists?
- From: "Alan Mason" <amason2 at austin.rr.com>
- Date: Wed, 1 Aug 2001 02:19:38 -0400 (EDT)
- References: <9k5r6g$hc1$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
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 > ----------------------------------------------------------------- > >