Authors: Kollotzek, Siegfried; Campos-Martinez, Jose; Bartolomei, Massimiliano; Pirani, Fernando; Tiefenthaler, Lukas; Hernandez, Marta, I; Lazaro, Teresa; Zunzunegui-Bru, Eva; Gonzalez-Lezana, Tomas; Breton, Jose; Hernandez-Rojas, Javier; Echt, Olof; Scheier, Paul


Publication date: 2022/12/21

DOI: 10.1039/d2cp03841b

Abstract: We report a novel method to reversibly attach and detach hydrogen molecules to positively charged sodium clusters formed inside a helium nanodroplet host matrix. It is based on the controlled production of multiply charged helium droplets which, after picking up sodium atoms and exposure to H-2 vapor, lead to the formation of Na-m(+)(H-2)(n) clusters, whose population was accurately measured using a time-of-flight mass spectrometer. The mass spectra reveal particularly favorable Na+(H-2)(n) and Na-2(+)(H-2)(n) clusters for specific magic numbers of attached hydrogen molecules. The energies and structures of these clusters have been investigated by means of quantum-mechanical calculations employing analytical interaction potentials based on ab initio electronic structure calculations. A good agreement is found between the experimental and the theoretical magic numbers.