Atomic Velocity Projection Method: A New Analysis Method for Vibrational Spectra in Terms of Internal Coordinates for a Better Understanding of XXXX Nanogrowth.

@entity10091 @entity74 @entity3440
UNASSIGNED: An efficient protocol is presented to identify signals in vibrational spectra of @entity3440 oligomers based on theoretical @entity74 ( @entity74 ) simulations. The method is based on the projection of the atomic velocity vectors on the tangential directions of the trajectories belonging to a predefined set of internal coordinates. In this way only contributions of atomic motions along these internal coordinates are taken into consideration. The new methodology is applied to the spectra of oligomers and rings, which play an important role in @entity10091 synthesis. A suitable selection of the relevant internal coordinates makes the protocol very efficient but relies on intuition and theoretical insight. The simulation data necessary to compute vibrational spectra of relevant @entity3440 species are obtained through @entity74 using proper force fields. The new methodology-the so-called velocity projection method-makes a detailed analysis of vibrational spectra possible by establishing a one-to-one correspondence between a spectral signal and a proper internal coordinate. It offers valuable perspectives in understanding the elementary steps in @entity3440 organization during @entity10091 nanogrowth. The so-called velocity projection method is generally applicable on data obtained from all types of @entity74 and is a highly valuable alternative to normal-mode analysis which has its limitations due to the presence of many local minima on the potential energy surface. In this work the method is exclusively applied to inelastic neutron scattering, but extension to the infrared power spectrum is apparent.
