Revisiting an old concept: the coupled oscillator model for VCD. Part 1: the generalised coupled oscillator mechanism and its intrinsic connection to the strength of VCD signals
| Autor: | Valentin Paul Nicu |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Physics
Work (thermodynamics) 010405 organic chemistry General Physics and Astronomy Expression (computer science) 010402 general chemistry 01 natural sciences 0104 chemical sciences Connection (mathematics) Mechanism (engineering) Theoretical physics Quantum mechanics Harmonic Physical and Theoretical Chemistry |
| Zdroj: | Physical chemistry chemical physics : PCCP. 18(31) |
| ISSN: | 1463-9084 |
| Popis: | Motivated by the renewed interest in the coupled oscillator (CO) model for VCD, in this work a generalised coupled oscillator (GCO) expression is derived by introducing the concept of a coupled oscillator origin. Unlike the standard CO expression, the GCO expression is exact within the harmonic approximation. Using two illustrative example molecules, the theoretical concepts introduced here are demonstrated by performing a GCO decomposition of the rotational strengths computed using DFT. This analysis shows that: (1) the contributions to the rotational strengths that are normally neglected in the standard CO model can be comparable to or larger than the CO contribution, and (2) the GCO mechanism introduced here can affect the VCD intensities of all types of modes in symmetric and asymmetric molecules. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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