Free Molecule Studies by Perturbed γ-γ Angular Correlation: A New Path to Accurate Nuclear Quadrupole Moments.

Heinz Haas,Patrick A Aggelund,Jens Röder,Doru C Lupascu,Vitor S Amaral,Lars B S Hemmingsen,Emil M H Larsen,Reiner Vianden,Rasmus Fromsejer,Abel S Fenta,Stephan P A Sauer,J Schell,Joao G Correia

doi:10.1103/physrevlett.126.103001

Abstract

Accurate nuclear quadrupole moment values are essential as benchmarks for nuclear structure models and for the interpretation of experimentally determined nuclear quadrupole interactions in terms of electronic and molecular structure. Here, we present a novel route to such data by combining perturbed γ-γ angular correlation measurements on free small linear molecules, realized for the first time within this work, with state-of-the-art abinitio electronic structure calculations of the electric field gradient at the probe site. This approach, also feasible for a series of other cases, is applied to Hg and Cd halides, resulting in Q(^{199}Hg,5/2^{-})=+0.674(17) b and Q(^{111}Cd,5/2^{+})=+0.664(7) b.

Highlights

Accurate nuclear quadrupole moment values are essential as benchmarks for nuclear structure models and for the interpretation of experimentally determined nuclear quadrupole interactions in terms of electronic and molecular structure
We present a novel route to such data by combining perturbed γ-γ angular correlation measurements on free small linear molecules, realized for the first time within this work, with state-of-the-art ab initio electronic structure calculations of the electric field gradient at the probe site
The perturbed γ-γ angular correlation (PAC) method has over the last 50 years become an established tool in materials physics for investigating magnetic fields and electric field gradient (EFG) in condensed matter, widely used in solid-state- [5], semiconductor- [6], surface- [7], and bio-physics [8] research

Summary

Introduction

Accurate nuclear quadrupole moment values are essential as benchmarks for nuclear structure models and for the interpretation of experimentally determined nuclear quadrupole interactions in terms of electronic and molecular structure. We present a novel route to such data by combining perturbed γ-γ angular correlation measurements on free small linear molecules, realized for the first time within this work, with state-of-the-art ab initio electronic structure calculations of the electric field gradient at the probe site.

Results

Conclusion