Improved Models for the Potential Energy Functions of the Ground Singlet and Lowest-Lying Triplet States of the Cesium Dimer

Cs₂;cesium dimer;potential energy function;scattering length;MLR;spectroscopy;Feshbach;Chemistry

Baldwin, Jesse

University of Waterloo

关键词: Cs₂;    cesium dimer;    potential energy function;    scattering length;    MLR;    spectroscopy;    Feshbach;    Chemistry;   

Others  :  https://uwspace.uwaterloo.ca/bitstream/10012/6872/3/Baldwin_Jesse_2012.pdf

瑞士|英语

来源: UWSPACE Waterloo Institutional Repository

【 摘 要 】

The Morse/Long Range (MLR) potential has become one of the most reliable and highlyused potential energy functions for diatomic molecules. It includes the theoretical long rangebehaviour that diatomic molecules are known to exhibit as they approach the dissociationlimit. Heavy alkali metals with adjacent electronic states often exhibit strong couplingbetween the spin and orbital angular momentum. The ground state X¹Σg⁺ and the lowestlying triplet state aᶟΣᵤ⁺ of Cs₂ exhibit such coupling effects and as a result, modeling thehighest vibrational states of these states is a non-trivial problem. Utilizing scattering lengthvalues obtained from published analysis of 60 Feshbach resonances, the correct form of thepotential energy function was determined. Moreover, the scattering length values were usedto determine the correct leading dispersion coefficient that describes the true form of thelong-range potential energy functions. All previous attempts to determine global potentialenergy functions for these states have considered only the optical spectroscopic data. This isthe first ever effort attempting to use scattering lengths determined from cold atom collisionexperiments in a combined analysis with conventional spectroscopic data.