dc.creator Abbate, S. en_US dc.creator Gussoni, M. en_US dc.creator Zerbi, Giusepp en_US dc.date.accessioned 2006-06-15T13:52:22Z dc.date.available 2006-06-15T13:52:22Z dc.date.issued 1976 en_US dc.identifier 1976-WD-4 en_US dc.identifier.uri http://hdl.handle.net/1811/9946 dc.description Author Institution: Istituto di Chimica delle Macromolecole del CNR en_US dc.description.abstract The intensity of infrared absorption for the i-th normal mode $\theta_{1}$ depends on $\left( \frac{\vec{\partial M}}{\partial Q_{i}} \right)^{\circ}$ where $\vec{M}$ is the total dipole moment of the molecule. $\left( \frac{\vec{\partial M}}{\partial Q_{i}} \right)^{\circ}$ can be expressed as $${\left( \frac{\vec{\partial M}}{\partial Q_{i}} \right)}^{\circ} = {\Sigma_{m}} {\left( \frac{\vec{\partial M}}{\partial R_{m}} \right)}^{\circ} \qquad L_{mi}$$, where $R_{m}$ is an internal coordinate, or as $$\left( \frac{\vec{\partial M}}{\partial Q_{i}} \right)^{\circ} = {\Sigma_{m}} \left\{ {\Sigma_{k}} {\left( \frac{\partial _{\mu^{k}}}{\partial R_{m}} \right)}^{\circ} \quad {\vec{e^{ko}}} + {\Sigma_{k}} \mu^{ko} {\left( \frac{\vec{\partial e^{k}}}{\partial R_{m}} \right)}^{\circ}\right\} \quad L_{mi}$$ where $\mu^{ko}$ and $\vec{e}^{ko}$ are the equilibrium bond dipole moments and equilibrium bond directions, respectively. ${\left( \frac{\partial \mu^{k}}{\partial R_{m}} \right)}^{\circ}$ and $\mu^{ko}$ are usually referred to as electrooptical parameters. The ${\left( \frac{\vec{\partial M}}{\partial R_{m}} \right)}^{\circ}$ can be transferred to isotopic derivatives only when $\vec{M^{\circ}}$ = 0; otherwise, they must be corrected for the rotational contributions. On the contrary the electrooptical parameters can be transferred to isotopic derivatives also when $\vec{M^{\circ}} \neq 0;$ moreover, since they refer to groups of atoms in the molecule, they seem more apt to be transferred to chemically similar molecules. Results will be presented of an overlay"" least squares refinement of the electrooptical parameters on the experimental intensity data of $CH_{4}, C_{2}H_{6}, C_{3}H_{8}$ and their isotopic derivatives. The same set of parameters successfully reproduces the infrared spectrum of polyethylene. en_US dc.format.extent 151348 bytes dc.format.mimetype image/jpeg dc.language.iso English en_US dc.publisher Ohio State University en_US dc.title TRANSFERABILITY OF ELECTRO-OPTICAL PARAMETERS FOR INFRARED INTENSITIES OF NORMAL PARAFFINS en_US dc.type article en_US
﻿