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We report an implementation for the computation of optical rotations within the Amsterdam Density Functional program package. The code is based on time-dependent density functional response theory. Optical rotations have been calculated for a test set of 36 organic molecules with various density functionals, and employing basis sets of different quality.(More)
We report the implementation of the computation of rotatory strengths, based on time-dependent density functional theory, within the Amsterdam Density Functional program. The code is applied to the simulation of circular dichroism spectra of small and moderately sized organic molecules, such as oxiranes, aziridines, cyclohexanone derivatives, and helicenes.(More)
Developing new forms of plastic and improving the efficiency of the catalysts that produce them requires detailed insight into the reaction steps in the polymerization process. This calls for thorough analysis and hefty computational resources. The authors discuss their strategies for accurate modeling, and Cobalt, a Beowulf supercomputer they built and(More)
In this paper, we describe our implementation of a combined Car-Parrinello and molecular mechanics method for the ab initio molecular dynamics simulations of extended systems. Since We have applied the method to determine the free energy barrier of the chain termination in a Ni-diimine based ethylene polymerization catalyst, 1. In this simulation the Ni(More)
We present the results of calculations on the vertical singlet (1)La and (1)Lb excitation energies in acenes within time dependent density functional theory (TDDFT), second order constricted variational DFT (CV(2)-DFT), and all order constricted variational DFT (CV(∞)-DFT) using the local density approximation LDA(VWN). For the linear acenes it is shown(More)
Density functional theory together with Car-Parrinello ab initio molecular dynamics simulation has been used to investigate the free energy profiles (FEP) of monomer capture in Grubbs- and SHOP-type olefin polymerization catalysts. The FEPs along the reaction coordinates at 300 K were determined directly by a point wise thermodynamic integration technique.(More)
not available. Ordinary time-dependent density functional theory (TDDFT) is not able to treat single excitations involving spin-flips and can thus not treat systems with spin generate ground state. We introduce in the first part of our talk a formulation of TDDFT based on a non-collinear representation of the XC potential. Within the non-collinear(More)
Orbital energies, ionization potentials, molecular constants, potential energy curves, and the excitation spectrum of O(2) are calculated using time-dependent density functional theory (TDDFT) with Tamm-Dancoff approximation (TDA). The calculated negative highest occupied molecular orbital energy (-epsilon(HOMO)) is compared with the energy difference(More)
The transition metal catalyzed ethylene polymerization in aqueous emulsion has been increasingly successful in the last couple of years. Water however adversely affects the polymerization process by (a) competing with ethylene for the binding site at the metal and (b) hydrolyzing the growing chain. Neutral salicylaldiminato and cationic diimine complexes of(More)
It is theoretically inappropriate to characterize an actively transporting epithelim by "resistance" alone which is correctly applied only to passive circuit elements. Rather, such epithelia (if they actively transport sodium) required, as a minimum, characterization by an active circuit element parameter such as voltage (E Na), current (I Na) or power(More)
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