Research output: Contribution to journal › Article

**The Jahn-Teller effect in the presence of partial isotopic substitution : the B ^{1}E" state of NH_{2}D and NHD_{2}.** / Saha, Ashim Kumar; Sarma, Gautam; Yang, Chung-Hsin; van de Meerakker, Sebastiaan; Parker, David H; Western, Colin M.

Research output: Contribution to journal › Article

Saha, AK, Sarma, G, Yang, C-H, van de Meerakker, S, Parker, DH & Western, CM 2015, 'The Jahn-Teller effect in the presence of partial isotopic substitution: the B^{1}E" state of NH_{2}D and NHD_{2}', *Physical Chemistry Chemical Physics*, vol. 21, pp. 14145-14158. https://doi.org/10.1039/C5CP01299F

Saha, A. K., Sarma, G., Yang, C-H., van de Meerakker, S., Parker, D. H., & Western, C. M. (2015). The Jahn-Teller effect in the presence of partial isotopic substitution: the B^{1}E" state of NH_{2}D and NHD_{2}. *Physical Chemistry Chemical Physics*, *21*, 14145-14158. https://doi.org/10.1039/C5CP01299F

Saha AK, Sarma G, Yang C-H, van de Meerakker S, Parker DH, Western CM. The Jahn-Teller effect in the presence of partial isotopic substitution: the B^{1}E" state of NH_{2}D and NHD_{2}. Physical Chemistry Chemical Physics. 2015 Jun 7;21:14145-14158. https://doi.org/10.1039/C5CP01299F

@article{83e9176c5a0a45ba9f8e80a1d2b59407,

title = "The Jahn-Teller effect in the presence of partial isotopic substitution: the B1E{"} state of NH2D and NHD2",

abstract = "Rotationally resolved resonance enhanced multiphoton ionisation spectra of the B1E{"} state of NH2D are presented and analysed. The analysis indicates a small (34.9 cm-1) lifting of the vibronic degeneracy of the zero point level, approximately equal in sign but opposite in magnitude to the splitting observed in NHD2 in previous work. This observation is consistent with previous measurements on systems with partial isotopic substitution subject to a mild Jahn-Teller effect. A model is developed to calculate the splitting induced by asymmetric isotopic substitution of a degenerate electronic state, based on a harmonic force field with linear and quadratic Jahn-Teller terms added. The force field is developed in internal co-ordinates to allow the same parameters to be used to calculate the pattern of vibronic levels for all four isotopologues. The lifting of the degeneracy of the zero point level on asymmetric substitution comes from the quadratic Jahn-Teller effect; the linear term does not lift the degeneracy.",

author = "Saha, {Ashim Kumar} and Gautam Sarma and Chung-Hsin Yang and {van de Meerakker}, Sebastiaan and Parker, {David H} and Western, {Colin M.}",

year = "2015",

month = "6",

day = "7",

doi = "10.1039/C5CP01299F",

language = "English",

volume = "21",

pages = "14145--14158",

journal = "Physical Chemistry Chemical Physics",

issn = "1463-9076",

publisher = "The Royal Society of Chemistry",

}

TY - JOUR

T1 - The Jahn-Teller effect in the presence of partial isotopic substitution

T2 - the B1E" state of NH2D and NHD2

AU - Saha, Ashim Kumar

AU - Sarma, Gautam

AU - Yang, Chung-Hsin

AU - van de Meerakker, Sebastiaan

AU - Parker, David H

AU - Western, Colin M.

PY - 2015/6/7

Y1 - 2015/6/7

N2 - Rotationally resolved resonance enhanced multiphoton ionisation spectra of the B1E" state of NH2D are presented and analysed. The analysis indicates a small (34.9 cm-1) lifting of the vibronic degeneracy of the zero point level, approximately equal in sign but opposite in magnitude to the splitting observed in NHD2 in previous work. This observation is consistent with previous measurements on systems with partial isotopic substitution subject to a mild Jahn-Teller effect. A model is developed to calculate the splitting induced by asymmetric isotopic substitution of a degenerate electronic state, based on a harmonic force field with linear and quadratic Jahn-Teller terms added. The force field is developed in internal co-ordinates to allow the same parameters to be used to calculate the pattern of vibronic levels for all four isotopologues. The lifting of the degeneracy of the zero point level on asymmetric substitution comes from the quadratic Jahn-Teller effect; the linear term does not lift the degeneracy.

AB - Rotationally resolved resonance enhanced multiphoton ionisation spectra of the B1E" state of NH2D are presented and analysed. The analysis indicates a small (34.9 cm-1) lifting of the vibronic degeneracy of the zero point level, approximately equal in sign but opposite in magnitude to the splitting observed in NHD2 in previous work. This observation is consistent with previous measurements on systems with partial isotopic substitution subject to a mild Jahn-Teller effect. A model is developed to calculate the splitting induced by asymmetric isotopic substitution of a degenerate electronic state, based on a harmonic force field with linear and quadratic Jahn-Teller terms added. The force field is developed in internal co-ordinates to allow the same parameters to be used to calculate the pattern of vibronic levels for all four isotopologues. The lifting of the degeneracy of the zero point level on asymmetric substitution comes from the quadratic Jahn-Teller effect; the linear term does not lift the degeneracy.

U2 - 10.1039/C5CP01299F

DO - 10.1039/C5CP01299F

M3 - Article

VL - 21

SP - 14145

EP - 14158

JO - Physical Chemistry Chemical Physics

JF - Physical Chemistry Chemical Physics

SN - 1463-9076

ER -