Iterative estimation of total π-electron energy

Download

10.2298:JSC0510193T.pdf

Date

2005

Author

Türker, Lemi
Gutman, Ivan

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

149
views

83
downloads

In this work, the lower and upper bounds for total -electron energy (E) was studied. A method is presented, by means of which, starting with a lower bound EL and an upper bound EU for E, a sequence of auxiliary quantities E0, E1, E2, … is computed, such that E0 = EL, E0 < E1 < E2 < …, and E = EU. Therefore, an integer k exists, such that Ek E < Ek+1. If the estimates EL and EU are of the McClelland type, then k is called the McClelland number. For almost all benzenoid hydrocarbons, k = 3.

Subject Keywords

General Chemistry, Total pi-electron energy, Bound for total pi-electron energy, McClelland number

URI

https://hdl.handle.net/11511/50880

Journal

Journal of the Serbian Chemical Society

DOI

https://doi.org/10.2298/jsc0510193t

Collections

Department of Chemistry, Article

Suggestions

OpenMETU
Core

The McClelland number of conjugated hydrocarbons Gutman, I; Türker, Burhan Lemi; Furtula, B; Vuckovic, V (2005-12-01) The McClelland number of a conjugated hydrocarbon is the integer k, satisfying the condition 2(-(1/2)k) root 2nm <= E < 2(-(1/2)k+1) root 2nm, where E is the HMO total pi-electron energy, n the number of carbon atoms, and m the number of carbon-carbon bonds. If k = 3, then the respective conjugated system is said to be energy-regular. If k ! 2 and k ! 4, then one speaks of energy-poor and energy-rich pi-electron systems, respectively. We found that all polycyclic Kekulean hydrocarbons, possessing condensed ...
Angle of graph energy - A spectral measure of resemblance of isomeric molecules Gutman, I; Türker, Burhan Lemi (2003-11-01) A method, elaborated earlier by one of the present authors, for measuring the structural resemblance of isomeric alternant conjugated hydrocarbons, based on a graph-spectral quantity theta, called the angle of total pi-electron energy approach has been extended now to arbitrary molecules. Some general properties of theta have been established.
Quadratically convergent algorithm for orbital optimization in the orbital-optimized coupled-cluster doubles method and in orbital-optimized second-order Moller-Plesset perturbation theory Bozkaya, Ugur; Turney, Justin M.; Yamaguchi, Yukio; Schaefer, Henry F.; Sherrill, C. David (2011-09-14) Using a Lagrangian-based approach, we present a more elegant derivation of the equations necessary for the variational optimization of the molecular orbitals (MOs) for the coupled-cluster doubles (CCD) method and second-order Moller-Plesset perturbation theory (MP2). These orbital-optimized theories are referred to as OO-CCD and OO-MP2 (or simply "OD" and "OMP2" for short), respectively. We also present an improved algorithm for orbital optimization in these methods. Explicit equations for response density ...
Polynomial solutions of the Schrodinger equation for the generalized Woods-Saxon potential Berkdemir, C; Berkdemir, A; Sever, Ramazan (American Physical Society (APS), 2005-08-01) The bound state energy eigenvalues and the corresponding eigenfunctions of the generalized Woods-Saxon potential are obtained by means of Nikiforov-Uvarov (NU) method. Certain bound states of the Schrodinger equation for the potential are calculated analytically and the wave functions are found in terms of the Jacobi polynomials. It is shown that the results are in good agreement with those obtained previously.
A novel approach to chemical resemblance of alternant hydrocarbons Türker, Burhan Lemi (2002-02-14) Within the constraints of the Huckel molecular orbital theory, a topological approach has been developed for the resemblance of alternant hydrocarbons. Four topological variables are considered which categorize alternant hydrocarbons having some resemblance of certain degree between them. Depending on variations of these topological variables, various groups of the compounds, including the identity case, various isomers and nonresembling systems have been investigated.

Citation Formats

L. Türker and I. Gutman, “Iterative estimation of total π-electron energy,” Journal of the Serbian Chemical Society, pp. 1193–1197, 2005, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/50880.