software makes inevitable rapid change for the use of 'molecular modeling' in chemistry. Molecular modeling will soon extend to 'reaction modeling', and students will uuderstand earlier and perhaps more intuitively what we have been asserting a t the chalkboard for so long. Imagine students in thc beginning organic course dismuaring resonance and hybridization, viwulizinji the reactivity of the carbonyl group, and calculating transition states for reactions. The accelerating trend toward more powerful desktop machines to make such calculations rapid and inexpensive shows no sign of abating. The time is right for dedicated classroom lecturers to review and revise the formal lecture approach in a serious way and introduce these new techniques. Note Added in Proof Wavefuntcion, Inc. (59) is publishing a software-independent text entitled Experiments in Computational Organic Chemistry [Hehre, W.; Burke, L. D.; Susterman, A. J.;Pietro, W. J. Wavefunction: Irvine, CA, 19931, which includes the first examples of "reaction modeling" as described in this paper. Gaussian Software (Carnegie Office Park, Bldg. 6, Pittsburgh, PA 15106)has released aversion of Gaussian 92 for Windows, making this application available at a modest price, although this software does not include a convenient eravhic interface. An instructional text J. B.; Frisch, A. Exploring accompanies it Chemistn, with Electronic Structure Methods: Gaussian:
man,
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