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Virginia Commonwealth University

DECKER SANDWICH

Publication Year

Articles 1 - 4 of 4

Full-Text Articles in Physics

Photoelectron Spectroscopy And Theoretical Studies Of [Com(Pyrene)N]− (M=1,2 And N=1,2) Complexes, Anil K. Kandalam, Puru Jena, Xiang Li, Soren N. Eustis, Kit H. Bowen Jan 2008

Photoelectron Spectroscopy And Theoretical Studies Of [Com(Pyrene)N]− (M=1,2 And N=1,2) Complexes, Anil K. Kandalam, Puru Jena, Xiang Li, Soren N. Eustis, Kit H. Bowen

Physics Publications

Anion photoelectron spectroscopic experiments and density functional theory based calculations have been used to investigate the structural, electronic, and magnetic properties of neutral and anionic [Com(pyrene)n] (m,n=1–2) complexes. The calculated electron affinities and vertical transition energies of Com(pyrene)n are in good agreement with the measured values. Our results provide clear evidence for dimerization of Co atoms and formation of sandwich structures in these complexes. While the calculated spin magnetic moments of neutral Co2(pyrene)n complexes suggest a preference for ferromagnetic coupling between Co atoms, the spin magnetic moment of Co atom in Co(pyrene) and Co(pyrene)2 complexes was reduced to 1μB.


Ground State Structures And Photoelectron Spectroscopy Of [Co-M(Coronene)](-) Complexes, Anil K. Kandalam, Boggavarapu Kiran, Puru Jena, Xiang Li, Andrej Grubisic, Kit H. Bowen Jan 2007

Ground State Structures And Photoelectron Spectroscopy Of [Co-M(Coronene)](-) Complexes, Anil K. Kandalam, Boggavarapu Kiran, Puru Jena, Xiang Li, Andrej Grubisic, Kit H. Bowen

Physics Publications

A synergistic approach involving theory and experiment has been used to study the structure and properties of neutral and negatively charged cobalt-coronene [Com(coronene)] complexes. The calculations are based on density functional theory with generalized gradient approximation for exchange and correlation potential, while the experiments are carried out using photoelectron spectroscopy of mass selected anions. The authors show that the geometries of neutral and anionic Co(coronene) and Co2(coronene) are different from those of the corresponding iron-coronene complexes and that both the Co atom and the dimer prefer to occupy η2-bridge binding sites. However, the magnetic coupling between the Co atoms remains …


Caging Of Ni Clusters By Benzene Molecules And Its Effect On The Magnetism Of Ni Clusters, B. K. Rao, P. Jena Jan 2002

Caging Of Ni Clusters By Benzene Molecules And Its Effect On The Magnetism Of Ni Clusters, B. K. Rao, P. Jena

Physics Publications

Global optimization of the geometry of small Ni clusters interacting with benzene molecules yields equilibrium structures where the Ni atoms find themselves caged between the benzene molecules. This leads to quenching of the Ni magnetic moment in most of the complexes even though the structure of the caged Ni clusters remain relatively unchanged from their otherwise free gas phase geometry. The accuracy of these predictions, based on density functional theory with generalized gradient approximation for exchange and correlation, is established by the good agreement achieved between the calculated and available experimental dissociation energies and ionization potentials.


Spectroscopy Of Ni-N(Benzene)(M) Anion Complexes, B. K. Rao, P. Jena Jan 2002

Spectroscopy Of Ni-N(Benzene)(M) Anion Complexes, B. K. Rao, P. Jena

Physics Publications

Total energy calculations based on the generalized gradient approximation to the density functional theory reveal that the Ni(benzene) and Ni(benzene)2 anions are unstable against autodetachment of the additional electron while other anion complexes containing more than one Ni atom are stable. Although the adiabatic electron affinities increase with Ni content, they are significantly smaller than those in pure Ni clusters containing the same number of Ni atoms. The difference between adiabatic electron affinities and vertical detachment energies are around 0.2 eV in most cases, indicating that the equilibrium geometries of Nin(benzene)−m are not significantly altered from their corresponding neutral geometries. …