8th International Conference on Vibrational Optical Activity

Schrödinger is excited to be participating in the 8th International Conference on Vibrational Optical Activity taking place on August 4th – 8th in Bochum, Germany. Join us for a presentation by Art Bochevarov, Research Leader at Schrödinger, titled “Judicious Selection of Conformers for VCD Spectra Prediction in Jaguar Spectroscopy Package.” Stop by our booth to speak with Schrödinger scientists.

Speaker:
Art Bochevarov, Research Leader, Schrödinger

Abstract:
A balanced selection of conformers is critical for practically useful prediction of VCD/IR spectra. A very large number of selected conformers may lead to prohibitive computational costs while choosing too few may result in an inadequate description of spectral details. To systematically study the effect of the number of selected conformers on the quality of simulated VCD spectra, we developed an algorithm for collating conformers from two arbitrary conformer sets. This tool allows us to compare 3D geometries of conformers generated by various software programs, and different settings thereof. We evaluate conformer generation programs MacroModel and CREST in the context of their efficacy for VCD spectra prediction. Another key element in an optimal selection of conformers is a computational filter. This computationally inexpensive energy function narrows the initial set of conformers down to a manageable subset, which is passed to final density functional calculations. Upon evaluating several such filters, we identify the neural network QRNN as the most promising one. Finally, we address the question of the number of conformers to be picked at various stages of the conformer selection process, as a function of the number of rotatable bonds in the molecule. The conclusions and the designed protocol are likely to be applicable to other types of Boltzmann-averaged spectral predictions implemented within our Jaguar Spectroscopy package, such as NMR.