Density functional study of the magnetic properties of Bi_{4}Mn clusters: Discrepancy between theory and experiment
Abstract
We have performed collinear and noncollinear calculations on neutral Bi_{4} Mn and collinear ones on ionized Bi_{4} Mn with charges +1 and 1 to find out why theoretical calculations will not predict the magnetic state found in the experiment. We have used the density functional theory to find a fit between the theoretical prediction of the magnetic moment and the experimental value. Our calculations have consisted in a structural search of local energy minima, and the lowest energy magnetic state for each resulting isomer. The geometry optimization found three local minima whose fundamental state is the doublet spin state. These isomers could not be found in previous theoretical works, but they are higher in energy than the lowestlying isomer by ≈1.75 eV. This magnetic state could help understand the experiment. Calculations of noncollinear magnetic states for the Bi_{4} Mn do not lower the total magnetic moment. We conclude arguing how the three isomers with doublet state could actually be the ones measured in the experiment.
 Publication:

Journal of Chemical Physics
 Pub Date:
 January 2011
 DOI:
 10.1063/1.3521270
 arXiv:
 arXiv:1007.0196
 Bibcode:
 2011JChPh.134c4307B
 Keywords:

 bismuth compounds;
 density functional theory;
 isomerism;
 magnetic moments;
 molecular clusters;
 36.40.Cg;
 33.15.Kr;
 31.15.es;
 Electronic and magnetic properties of clusters;
 Electric and magnetic moments polarizability and magnetic susceptibility;
 Applications of densityfunctional theory;
 Condensed Matter  Mesoscale and Nanoscale Physics
 EPrint:
 11 pages, 6 figures