CHINESE JOURNAL OF PHYSICS VOL. 50, NO. 1 February 2012 Geometrical Electronic, and Vibrational Properties of Fullerene Rings Doped with Transition Metals Neeraj Misra, * Apoorva Dwivedi, and Anoop Pandey Department of Physics, Lucknow University, Lucknow 226007, India (Received August 7, 2010) Fullerene derivatives have been shown to make contributions in many types of applications. The structure and vibrational spectra of fullerene rings doped with transition metals were investigated by the PM3 molecular modeling technique. The doping effect is discussed in terms of the change in the C-C bond lengths, net atomic charge distribution, total dipole moment, vibrational frequencies, and conductivity. The obtained results indicate that the C-C distances are enlarged as a result of doping. Furthermore, there is a complete change in the net atomic charge distribution, as well as a corresponding increase in the value of the total dipole moment. So, if we want to increase the conductivity of fullerene rings, the number of C atoms should be increased along with a suitable doping element, by which we find a higher charge density in a specific plane. PACS numbers: 31.15.bu, 72.80Rj I. INTRODUCTION The discovery [1] of ‘buckyballs’ C 60 has stimulated a great deal of research. Their macroscopic preparation [2] has opened multiple research areas, now commonly embraced under the label of ‘fullerene chemistry’. It is well known that the C 60 molecule may have unusual magnetic properties. The C 60 class of compounds possesses an ambiguous aro- matic character; traditional measures are often inadequate for its proper classification [3]. Fullerene based nanojunctions are emerging as fascinating systems for basic research that may also find application as components for future nanodevices [4]. Modeling techniques help to pave the way toward understanding the physical properties of fullerenes and fullerene derivatives. In another study, ab initio calculations were used to investigate the structural and electronic properties of small silicon clusters as well as endohedral metallofullerenes [5]. Semi-empirical, ab initio, and density functional theory (DFT) studies on the structures and stabilities of C 60 CH 2 isomers have also been reported [6]. In addition, ab initio cal- culations on MC 60 (M=Sc, Y, and K) were done to evaluate the stability of this type of metallofullerene molecule [7]. In the literature, semi-empirical calculations were proposed to study the structure and vibrational properties of C 60 ,C 80 , and their epoxides [8]. The same research group also carried out studies in the doping of C 60 with Si, Ge, and Al, and it was reported that C 60 , when doped with an element whose atom has 4 valence electrons, resulted in a change in certain electrical and magnetic properties [9]. Also, it has been shown that * Electronic address: neerajmisra@hotmail.com http://PSROC.phys.ntu.edu.tw/cjp 64 c ⃝ 2012 THE PHYSICAL SOCIETY OF THE REPUBLIC OF CHINA