Tailoring one dimensional novel nano structures for specific applications using tools of molecular modeling

Download
2008
Malcıoğlu, Osman Barış
In this work, the use of theoretical tools of molecular modeling for tailoring 1D novel nanomaterials is demonstrated. There are four selected nano-structures as examples, each tailored for a speci c demand of nano-technology that is yet to be ful lled. For the purpose of modeling/calculating the electronic and structural properties, various methods of de ning the interatomic interaction, such as empirical potential energy functions, semi-empirical methods and density functional theory, are used. Each of these methods have a di erent level of approximations leading to limitations in their use. Furthermore, each method needs to be calibrated carefully in order to obtain physically meaningful results. Examples being novel nano-structures, there does not exist any experimental observations directly studying the material at hand. Thus, in order to obtain a parameter set that best describes the system, a series of pre-existing structures that are physically and/or chemically related are used. Among the methods employed, the density functional theory (DFT) is certainly the most popular one, due to its accuracy and more importantly the framework it provides for perturbative extensions otherwise nearly impossible to calculate in Hartree-Fock level.

Suggestions

Measurement of tau polarization in W -> tau nu decays with the ATLAS detector in pp collisions at root s=7 TeV
Aad, G.; et. al. (2012-07-01)
In this paper, a measurement of tau polarization in W -> tau nu decays is presented. It is measured from the energies of the decay products in hadronic tau decays with a single final state charged particle. The data, corresponding to an integrated luminosity of 24 pb(-1), were collected by the ATLAS experiment at the Large Hadron Collider in 2010. The measured value of the tau polarization is P-tau = -1.06 +/- 0.04 (stat)(-0.07)(+0.05) (syst), in agreement with the Standard Model prediction, and is consiste...
Development of atomic force microscopy system and kelvin probe microscopy system for use in semiconductor nanocrystal characterization
Bostancı, Umut; Turan, Raşit; Department of Physics (2007)
Atomic Force Microscopy (AFM) and Kelvin Probe Microscopy (KPM) are two surface characterization methods suitable for semiconductor nanocrystal applications. In this thesis work, an AFM system with KPM capability was developed and implemented. It was observed that, the effect of electrostatic interaction of the probe cantilever with the sample can be significantly reduced by using higher order resonant modes for Kelvin force detection. Germanium nanocrystals were grown on silicon substrate using different g...
Development of software for calculations of the reflectance, transmittance and absorptance of multilayered thin films
Şimşek, Yusuf; Esendemir, Akif; Department of Physics (2008)
The aim of this study is to develop a software which calculates reflection, transmission and absorption of multilayered thin films by using complex indices of refraction, as a function of both wavelength and thickness. For these calculations matrix methods will be considered and this software is programmed with the matrix method. Outputs of the program will be compared with the theoretical and experimental results studied in the scientific papers.
Mems gyroscopes for tactical-grade inertial measurement applications
Alper, Said Emre; Akın, Tayfun; Department of Electrical and Electronics Engineering (2005)
This thesis reports the development of high-performance symmetric and decoupled micromachined gyroscopes for tactical-grade inertial measurement applications. The symmetric structure allows easy matching of the resonance frequencies of the drive and sense modes of the gyroscopes for achieving high angular rate sensitivity; while the decoupled drive and sense modes minimizes mechanical cross-coupling for low-noise and stable operation. Three different and new symmetric and decoupled gyroscope structures with...
Hamilton-Jacobi theory of continuous systems
Güler, Y. (Springer Science and Business Media LLC, 1987-8)
The Hamilton-Jacobi partial differnetial equation for classical field systems is obtained in a 5n-dimensional phase space and it is integrated by the method of characteristics. Space-time partial derivatives of Hamilton’s principal functionsS μ (Φ i ,x ν ) (μ,ν=1,2,3,4) are identified as the energy-momentum tensor of the system.
Citation Formats
O. B. Malcıoğlu, “Tailoring one dimensional novel nano structures for specific applications using tools of molecular modeling,” Ph.D. - Doctoral Program, Middle East Technical University, 2008.