Ca impurity in small mixed He-4-He-3 clusters

The structure of small mixed helium clusters doped with one calcium atom has been determined within the diffusion Monte Carlo framework. The results show that the calcium atom sits at the He-4-He-3 interface. This is in agreement with previous studies, both experimental and theoretical, performed fo...

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Detalles Bibliográficos
Autores: Guardiola, Rafael, Navarro Faus, Jesús, Mateo, David, Barranco, Manuel
Tipo de recurso: artículo
Fecha de publicación:2009
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/20770
Acceso en línea:http://hdl.handle.net/10261/20770
Access Level:acceso abierto
Palabra clave:Atomic clusters
Calcium
helium
impurities
impurity absorption spectra
Monte Carlo methods
quantum fluids
Descripción
Sumario:The structure of small mixed helium clusters doped with one calcium atom has been determined within the diffusion Monte Carlo framework. The results show that the calcium atom sits at the He-4-He-3 interface. This is in agreement with previous studies, both experimental and theoretical, performed for large clusters. A comparison between the results obtained for the largest cluster we have considered for each isotope shows a clear tendency of the Ca atom to reside in a deep dimple at the surface of the cluster for He-4 clusters, and to become fully solvated for He-3 clusters. We have calculated the absorption spectrum of Ca around the 4s4p <- 4s(2) transition and have found that it is blueshifted from that of the free-atom transition by an amount that depends on the size and composition of the cluster.