Penn State Science
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Graphene on Silica
O Diffusion on Graphene
Variable range hopping
Water/Metal Oxides
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Electronic density of the C3v MetCar

Nanoclusters are novel building blocks for structured materials. We study the structural, electronic, and vibrational properties of Ti8C12 metallocarbohedrynes. Density Functional Theory (DFT) calculations are performed to study the low energy isomers of the Ti8C12 metallocarbohedrynes using spin polarized DFT, where we find a correlation between the number of rotated carbon dimers and the cohesive energy. The C3v, D*3d and D3d isomers are spin polarized. Depending on the dimer orientation, carbon atoms and a sub group of the metal atoms form a covalent framework while other metal atoms are bonded to this framework more ionically. This picture is further supported by the charge density of the different structures, where we see that the Ti atoms with higher charge density show less contribution to the covalent bonding of the Ti-C framework. The vibrational spectra are calculated using the frozen-vibration method and ab-initio molecular dynamics simulations at different temperatures. The results demonstrate the local stability of the structures beyond the harmonic limit explored by the frozen-vibration method. We are currently analyzing the possibility of synthesizing solids made of MetCars as building blocks.

This research area provides opportunities for undergraduate research.


2005 · 2006 · 2007 · 2011 · 2012 · All
I. Iordanov, K. Gunaratne, C. L. Harmon, J. O. Sofo and W. Castleman, "Broad photoelectron spectrum and lowered electron affinity due to Hydrogen in ZnOH: A joint experimental and theoretical study," J. Chem. Phys. 136, 214314 (2012)
C. Berkdemir, W. Castleman and J. O. Sofo, "Metal-substituted Ti8C12 metallocarbohedrynes: Toward less reactive clusters as building blocks of cluster-assembled materials," Phys. Chem. Chem. Phys. 14, 9642 – 9653 (2012)
I. Iordanov and J. O. Sofo, "Multiple Isomers in the Photoelectron Spectra of Small Mono-Niobium Carbide Clusters," J. Chem. Phys. 134, 184310 (2011)
H. Kim, J. O. Sofo, D. Velegol, M. W. Cole and A. Lucas, "Van der Waals Dispersion Forces between Dielectric Nanoclusters," Langmuir 23, 1735 – 1740 (2007)
K. L. Knappenberger, P. A. Clayborne, J. U. Reveles, M. A. Sobhy, C. E. Jones, U. U. Gupta, S. N. Khanna, I. Iordanov, J. O. Sofo and W. Castleman, "Anion Photoelectron Spectroscopy and Density Functional Investigation of Diniobium−Carbon Clusters," ACS Nano 1, 319 – 326 (2007)
K. L. Knappenberger, C. E. Jones, M. A. Sobhy, I. Iordanov, J. O. Sofo and W. Castleman, "Anion Photoelectron Spectroscopy and Density Functional Investigation of Vanadium Carbide Clusters," J. Phys. Chem. A 110, 12814 – 12821 (2006)
M. A. Sobhy, W. Castleman and J. O. Sofo, "A density functional study of the structural, electronic, magnetic, and vibrational properties of Ti8C12 metallocarbohedrynes," J. Chem. Phys. 123, 154106 (2005)

Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

J. O. Sofo : Properties of Small Metal/Carbon Clusters