Precision measurement of the fundamental vibrational frequencies of tritium-bearing hydrogen molecules: T2, DT, HT

K.-F. Lai, V. Hermann, T. M. Trivikram, M. Diouf, M. Schlösser, W. Ubachs, E. J. Salumbides*

*Corresponding author for this work

Research output: Contribution to JournalArticleAcademicpeer-review

29 Downloads (Pure)

Abstract

High-resolution coherent Raman spectroscopic measurements of all three tritium-containing molecular hydrogen isotopologues T2, DT and HT were performed to determine the ground electronic state fundamental Q-branch (v= 0 → 1, ΔJ= 0) transition frequencies at accuracies of 0.0005 cm−1. An over hundred-fold improvement in accuracy over previous experiments allows the comparison with the latestab initiocalculations in the framework of non-adiabatic perturbation theory including nonrelativisitic, relativisitic and QED contributions. Excellent agreement is found between experiment and theory, thus providing a verification of the validity of the NAPT-framework for these tritiated species. While the transition frequencies were corrected for ac-Stark shifts, the contributions of non-resonant background as well as quantum interference effects between resonant features in the nonlinear spectroscopy were quantitatively investigated, also leading to corrections to the transition frequencies. Methods of saturated CARS with the observation of Lamb dips, as well as the use of continuous-wave radiation for the Stokes frequency were explored, that might pave the way for future higher-accuracy CARS measurements.

Original languageEnglish
Pages (from-to)8973-8987
Number of pages15
JournalPhysical Chemistry Chemical Physics
Volume22
Issue number16
Early online date25 Mar 2020
DOIs
Publication statusPublished - 28 Apr 2020

Fingerprint

Dive into the research topics of 'Precision measurement of the fundamental vibrational frequencies of tritium-bearing hydrogen molecules: T2, DT, HT'. Together they form a unique fingerprint.

Cite this