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Aufsatz
Auger spectroscopy of foil-excited beryllium ions
(Kleinpoppen, H. (Hrsg.), 1976)
We have measured prompt and delayed emission spectra of electrons from foilexcited Be, B^+, and Be^2+ ions at 300 keV. On the basis of recently calculated eigenvalues we identified two lines in the prompt Be^+ spectrum as transitions from 2s^22p and 2s2p^2. The delayed Be spectrum indicates that transitions from highly excited quintet states occur. We propose radiationless deexcitation with one excited spectator electron not involved in the transition.
Dissertation
Protein Folding Simulations: Confinement, External Fields and Sequence Design
(2010-04-08)
The present Thesis looks at the problem of protein folding using Monte Carlo and Langevin simulations, three topics in protein folding have been studied:
1) the effect of confining potential barriers,
2) the effect of a static external field and
3) the design of amino acid sequences which fold in a short time and which have a stable native state (global minimum).
Regarding the first topic, we studied the confinement of a small protein of 16 amino acids known as 1NJ0 (PDB code) which has a beta-sheet ...
Aufsatz
Predicted properties of the superheavy elements. III. Element 115, Eka-Bismuth
(1974)
Element 115 is expected to be in group V-a of the periodic table and have most stable oxidation states of I and III. The oxidation state of I, which plays a minor role in bismuth chemistry, should be a major factor in 115 chemistry. This change will arise because of the large relativistic splitting of the spherically symmetric 7p_l/2 shell from the 7P_3/2 shell. Element 115 will therefore have a single 7p_3/2 electron outside a 7p^2_1/2 closed shell. The magnitude of the first ionization energy and ionic radius suggest ...
Aufsatz
Predicted properties of the superheavy elements, II. Element 111, Eka-Gold
(1973)
The chemical properties of element 111, eka-gold, are predicted through the use of the periodic table, relativistic Hartee-Fock-Slater calculations, and various qualitative theories which have established their usefulness in understanding and correlating properties of molecules. The results indicate that element 111 will be like Au(III) in its chemistry with little or no tendency to show stability in the I or II states. There is a possibility that the 111 - ion, analogous to the auride ion, will be stable.
Aufsatz
Theoretical study of the physicochemical properties of the light transactinides
(1994)
A theoretical study of the physicochemical properties of elements 104, 105, and 106 and their compounds in the gas phase and aqueous solutions has been undertaken using relativistic atomic and molecular codes. Trends in properties such as bonding, ionization potentials, electron affinities, energies of electronic transitions, stabilities of oxidation states etc. have been defined within the corresponding chemical groups and within the transactinides.
These trends are shown to be determined by increasing relativistic ...
Aufsatz
Intrinsic channel closing in strong-field single ionization of H2
(American Physical Society, 2008-04-08)
Die Ionisation von H2 in intensiven Laserpulsen wird mit Hilfe der numerischen Integration der zeitabhängigen Schrödingergleichung für ein Einelektronenmodell untersucht, das die Vibrationsbewegung berücksichtigt. Die Spektren der kinetischen Elektronenenergie hängen stark von der Vibrationsquantenzahl des erzeugten H2+ Ions ab. Für bestimmte Vibrationszustände ist die Ausbeute der Elektronen in der Mitte des Plateaus stark erhöht. Der Effekt wird "channel closings" zugeschrieben, die in Atomen durch Variation der ...
Aufsatz
Transitions between quintet states of doubly excited four-electron ions
(1990)
Following an earlier observation in F VI we identified the line pair 1s2s2p^2 {^5P}-1s2s2p3d {^5P^0}
, {^5D^0} for the elements N, O, Mg, and tentatively for A1 and Si in beam-foil spectra. Assignment was established by comparison with Multi-Configuration Dirac-Fock calculations along the isoelectronic sequence. Using this method we also identified some quartet lines of lithium-like ions with Z > 10.
Aufsatz
Interpretation of the anisotropy of M MO radiation in slow I on Au collisions
(1979)
A comparison between experimental and calculated spectral shape and energy dependence of the M MO x-ray anisotropy in heavy-ion collisions of I on Au is presented. The calculation is performed within the kinematic-dipole model of anisotropy using MO x-rays determined from SCF relativistic correlation diagrams.
Aufsatz
Evidence for an additional coupling of the innermost shells in very heavy quasi-molecular ion-atom collisions
(1982)
Due to the tremendous spin-orbit splitting of quasi-molecular levels in superheavy collision systems (Z = Z_1 + Z_2 {\ge\approx} 137) bombarding energy 0.5-6 MeV N{^-1}, unusual couplings may occur around Z \simeq 165. Experimental evidence for such a theoretically predicted coupling is discussed.
Aufsatz
Calculations of the polycentric linear molecule H^2+_3 with the finite element method
(1993)
A fully numerical two-dimensional solution of the Schrödinger equation is presented for the linear polyatomic molecule H^2+_3 using the finite element method (FEM). The Coulomb singularities at the nuclei are rectified by using both a condensed element distribution around the singularities and special elements. The accuracy of the results for the 1\sigma and 2\sigma orbitals is of the order of 10^-7 au.