In this question you will use the one-dimensional particles in a box model to approximate the absorption wavelength of a cyanine dye. To determine the "box-length" for the model, determine the total length along the conjugated part of the molecule (both single and double bonds) use the following bond lengths: Typical CC bond length (both single/double bond) = 0.14 nm Typical CN bond length (both single/double bond) = 0.13 nm The structure of a cyanine dye is shown below. You need to determine the wavelength of light for a cyanine dye with n=8. Consider that both nitrogens are conjugated, so consider two CN bonds when determining box length. The left-most nitrogen has two electrons (lone pair) that count towards the number of electrons in the box, but the right-most nitrogen has no lone pair, just the double-bond. Provide your answer as the wavelength of light absorbed in units of nm. R R n R R

In this question you will use the one-dimensional particles in a box model to approximate the absorption wavelength of a cyanine dye. To determine the "box-length" for the model, determine the total length along the conjugated part of the molecule (both single and double bonds) use the following bond lengths: Typical CC bond length (both single/double bond) = 0.14 nm Typical CN bond length (both single/double bond) = 0.13 nm The structure of a cyanine dye is shown below. You need to determine the wavelength of light for a cyanine dye with n=8. Consider that both nitrogens are conjugated, so consider two CN bonds when determining box length. The left-most nitrogen has two electrons (lone pair) that count towards the number of electrons in the box, but the right-most nitrogen has no lone pair, just the double-bond. Provide your answer as the wavelength of light absorbed in units of nm. R R n R R

Physical Chemistry

2nd Edition

ISBN:9781133958437

Author:Ball, David W. (david Warren), BAER, Tomas

Publisher:Ball, David W. (david Warren), BAER, Tomas

Chapter15: Introduction To Electronic Spectroscopy And Structure

Section: Chapter Questions

Problem 15.69E

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