DFT Study of a Novel Organic Film: The Structural versus Magnetic Effects

S. SIMONETTI; A. JUAN; G. BRIZUELA; S. ULACCO

Advances in Physical Chemistry

Hindawi Publishing Corporation

Lugar: Cairo; Año: 2015

Unsaturated fatty acids have great interest by their activities as industrial materials in novel applications. In the present work, thecis-3-hexenoic acid (HA) adsorbed on the Ni(111) surface was studied by first-principles calculations using the Vienna Ab InitioSimulation Package (VASP). The most stable location for HA is presented on top site of Ni(111), although the energies are verysimilar for all the adsorption sites.Thesurface-molecule interaction takes place between the carboxyl group ofHA and surroundingNi atoms. The adsorption is weak and consequently the metal-molecule length is enhanced.The carboxyl group is elongated andweakened after adsorption giving rise to a shift in stretching frequencies.There are notable changes on themagneticmoments valuesof Ni surface atoms neighboring to the molecule that mainly induced magnetic moments on O and H atoms. Noticeable chargetransfer occurs in 3d 4s, p Ni orbitals and 2s C, 2s p O, 1s H orbitals of carboxyl group.The surface presents positive work functionchanges after adsorption as a consequence of an electron back-donation.During interaction, the significance of themagnetic effectsover the structural effects is evidenced.This sets the stage for a future adsorption process improvement based on the modificationof the surface magnetic properties.