Browsing by Author "Ozdogan, C"

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Citation - WoS: 10
Citation - Scopus: 1
(Formula Presented) Algorithms In Tight-Binding Molecular-Dynamics Simulations of the Electronic Structure of Carbon Nanotubes
(American Physical Soc, 2003) Dereli, G; Özdoğan, Cem; Ozdogan, C; 40569; Ortak Dersler Bölümü
The O(N) and parallelization techniques have been successfully applied in tight-binding molecular-dynamics simulations of single-walled carbon nanotubes (SWNT's) of various chiralities. The accuracy of the O(N) description is found to be enhanced by the use of basis functions of neighboring atoms (buffer). The importance of buffer size in evaluating the simulation time, total energy, and force values together with electronic temperature has been shown. Finally, through the local density of state results, the metallic and semiconducting behavior of (10x10) armchair and (17x0) zigzag SWNT's, respectively, has been demonstrated.
Citation - WoS: 68
Citation - Scopus: 87
O(N) algorithms in tight-binding molecular-dynamics simulations of the electronic structure of carbon nanotubes
(Amer Physical Soc, 2003) Dereli, G; Özdoğan, Cem; Ozdogan, C; 40569; Ortak Dersler Bölümü
A (10x10) single-walled carbon nanotube consisting of 400 atoms with 20 layers is simulated under tensile loading using our developed O(N) parallel tight-binding molecular-dynamics algorithms. It is observed that the simulated carbon nanotube is able to carry the strain up to 122% of the relaxed tube length in elongation and up to 93% for compression. Young's modulus, tensile strength, and the Poisson ratio are calculated and the values found are 0.311 TPa, 4.92 GPa, and 0.287, respectively. The stress-strain curve is obtained. The elastic limit is observed at a strain rate of 0.09 while the breaking point is at 0.23. The frequency of vibration for the pristine (10x10) carbon nanotube in the radial direction is 4.71x10(3) GHz and it is sensitive to the strain rate.