Biomedical subjects

Jörg Breidbach

Publications and source records attributed to Jörg Breidbach.

4 recordsLinked to original sources

PubMed2005

Multielectron wave-packet propagation: general theory and application.

An ab initio method for multielectron wave-packet propagation in relatively large systems is presented. It allows the description of ultrafast electron dynamics processes before the coupling with the nuclear motion becomes important. The method is applied to the amino acid glycine for the investigation of the migration of hole charge following the ionization of the system. Two different mechanisms of ultrafast charge migration are identified and discussed. It is shown that the electron correlation can be the driving force for the charge-transfer dynamics in glycine.

Journal Article↗

PubMed2005

Charge transfer driven by electron correlation: a non-Dyson propagator approach.

A hole charge created in a molecular system, for instance, by ionization, can migrate through the system solely driven by electron correlation. This charge transfer due to electron correlation is referred to as charge migration. We introduce in this work a new ab initio method analyzing charge migration due to electron correlation in molecules. This method, a third-order "non-Dyson" propagator approach, aims in the long run, in particular, at the calculation of charge migration in relatively large molecules such as oligopeptides. First results of the new non-Dyson method are compared with a previously used propagator approach.

Journal Article↗

PubMed2005

Remarkable interplay of electron correlation and relativity in the photodetachment spectrum of PtCl(6)2-.

In this work we calculate the photoelectron spectrum of the PtCl(6) (2-) dianion by application of the recently developed third-order Dirac-Hartree-Fock implementation of the one-particle propagator technique allowing for a consistent treatment of spin-orbit and scalar relativistic effects together with electron correlation. For PtCl(6) (2-) a gas phase photoelectron spectrum is available showing clearly discernible structures not reproducible by a nonrelativistic or purely scalar-relativistic computation. A population analysis of the valence orbitals allows for an assignment of the photoelectron peaks and reveals the strong influence of relativity in combination with electron correlation.

Journal Article↗

PubMed2005

Electron correlation as the driving force for charge transfer: charge migration following ionization in N-methyl acetamide.

A hole charge created in a molecule, for instance, by ionization, can migrate through the system solely driven by electron correlation. The migration of a hole charge following ionization in N-methyl acetamide (a molecular system containing a peptide bond) is investigated. The initial hole charge is localized at one specific site of the molecule. Ab initio calculations show that nearly 90% of the hole migrates to a remote site of the molecule in 4.2 fs. This migration of charge is highly efficient and ultrafast. The underlying mechanism for this migration of a hole charge is identified and compared with a simple model.

Acetamides↗