RESEARCH PAPER Vibrational analysis and thermodynamic properties of C 120 nanotorus: a DFT study Ernesto Lo ´pez-Cha ´vez • Armando Cruz-Torres • Fray de Landa Castillo-Alvarado • Jaime Ortı ´z-Lo ´pez • Ye ´sica A. Pen ˜ a-Castan ˜eda • Jose ´ Manuel Martı ´nez-Magada ´n Received: 18 May 2011 / Accepted: 8 September 2011 / Published online: 1 October 2011 Ó Springer Science+Business Media B.V. 2011 Abstract Density functional theory (DFT) compu- tational methods are applied to a C 120 carbon nanoto- rus studied as an isolated molecular species, using the functional GGA PW91. This toroidal form of carbon contains five fold, six fold, and sevenfold rings. The calculated cohesive energy of the nanotorus, indicates that the ground state of this structure is energetically more stable than that of fullerene C 60 . Geometry and stability, Raman and IR vibrational analysis and thermodynamic properties have been reported and compared to the values obtained by other authors. Keywords Density functional theory (DFT)  Carbon nanotorus C 120  Molecular simulations  Energetic  Vibrational analysis  Thermodynamic properties  Modeling and simulation Introduction Since the discovery of fullerene C 60 (Kroto et al. 1985) in 1985 and of carbon nanotubes in 1991 (Iijima 1991), carbon nanostructures have generated great interest among researchers. A great number of studies on the structural and physical properties of this kind of materials (Saito et al. 1998) have been carried out over the last two decades. The results of these studies show the beginning of a new scientific and technological revolution for the 21st century (Trauzettel et al. 2007; Son et al. 2005; Qin et al. 2003). At the beginning of the 90 s, a toroidal carbon structure was theoretically proposed by Dunlap (Dunlap 1992, Dunlap 1994: The concept of this form was obtained out of the consid- eration of the dangling bonds in a carbon nanotube). Since then, some other authors have proposed models of toroidal carbon nanotubes. E. Lo ´pez-Cha ´vez (&) Programa de Ingenierı ´a Molecular y Nuevos Materiales de la Universidad Auto ´noma de la Ciudad de Me ´xico, Academia de Fı ´sica. Av. Fray Servando Teresa de Mier 92-110, Col. Centro Histo ´rico, Delegacio ´n Cuauhte ´moc, 06080 Me ´xico, DF, Mexico e-mail: elopezc_h@hotmail.com A. Cruz-Torres  F. de Landa Castillo-Alvarado  J. Ortı ´z-Lo ´pez  Y. A. Pen ˜a-Castan ˜eda Escuela Superior de Fı ´sica y Matema ´ticas del Instituto Polite ´cnico Nacional. Edificio 9 de la Unidad Profesional Adolfo Lo ´pez Mateos, Col. Lindavista, Delegacio ´n Gustavo A. Madero, 07738 Me ´xico, DF, Mexico e-mail: acruztorres@yahoo.com.mx F. de Landa Castillo-Alvarado e-mail: fray@esfm.ipn.mx J. Ortı ´z-Lo ´pez e-mail: jortiz@esfm.ipn.mx Y. A. Pen ˜a-Castan ˜eda e-mail: pcastaeda@yahoo.com J. M. Martı ´nez-Magada ´n Instituto Mexicano del Petro ´leo, Eje Central La ´zaro Ca ´rdenas Norte 152, Col. San Bartolo Atepehuaca ´n, 07730 Me ´xico, DF, Mexico e-mail: mmartine@imp.mx 123 J Nanopart Res (2011) 13:6649–6659 DOI 10.1007/s11051-011-0572-z