Eur. Phys. J. D 47, 171-179 (2008)
https://doi.org/10.1140/epjd/e2008-00045-y

Improved potentials and Born-Oppenheimer corrections by new measurements of transitions of ¹²⁹I₂ and ¹²⁷I¹²⁹I  in the B³Π_0⁺u - X¹Σ⁺_g band system^*

¹ Laser Centre Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
² Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
³ Institut für Quantenoptik, Leibniz Universität Hannover, Welfengarten 1, 30167 Hannover, Germany

Corresponding author: ^a knoeckel@iqo.uni-hannover.de

Received: 26 October 2007
Revised: 7 February 2008
Published online: 14 March 2008

Abstract

The light from one single frequency cw laser was employed in a double saturation spectroscopy experiment to record high resolution spectra of ¹²⁹I₂ and ¹²⁷I¹²⁹I together with spectra of ¹²⁷I₂ which is used as a simultaneous frequency reference. Two separate saturation spectroscopy set ups were used. The frequencies of lines of ¹²⁹I₂ and ¹²⁷I¹²⁹I were determined with respect to lines of ¹²⁷I₂. More than 380 frequency differences between lines of ¹²⁷I₂ and of the other isotopomers have been included in the data set. By a direct potential fit a precise description of the potential energy curves of the B and the X state and of effective Born-Oppenheimer correction functions valid for all three isotopomers of I₂ are given.