Problem definiowania w naukach humanistycznych

tekst zamieszczony w czasopiśmie "Zdrowie psychiczne", nr 1-2/1993

Naukowiec jako polityk. O argumentacji perswazyjnej i nie tylko

tekst zamieszczony w czasopiśmie "Nauka i Szkolnictwo Wyższe", nr 1/25/2005

Electronic correlations in organometallic complexes

We investigate an effective model for organometallic complexes (with potential uses in optoelectronic devices) via both exact diagonalisation and the configuration interaction singles (CIS) approximation. This model captures a number of important features of organometallic complexes, notably the sensitivity of the radiative decay rate to small chemical changes. We find that for large parameter ranges the CIS approximation accurately reproduces the low energy excitations and hence the photophysical properties of the exact solution. This suggests that electronic correlations do \emph{not} play an important role in these complexes. This explains why time-dependent density functional theory works surprisingly well in these complexes.Comment: 11 pages, 6 figure

Memorandum de Entendimiento entre la Univerisidad Autonoma Agraria "Antonio Narro" y el Programa de Trigo del Centro Internacional de Mejoramiento de Maiz y Trigo, para Desarrollar un Proyecto Conjunto de Investigacion en Triticale Forrajero

MOU between CIMMYT and la Universidad Autonoma Agraria signed March 14, 1996 regarding cooperation in a research program. MOU is in Spanish and contains two annexes

Ontologia epistemologii

Ingarden’s puzzle is: how can we come to know what is essentially involved in an act of knowing? As starting point he takes what he holds to be a particular good candidate example of such an act, namely an act of perceiving an apple. Here we have act and object standing in a certain first-level relation to each other. We now in a second level act of reflection, make this first-level relation into an object, and strive to apprehend this object as an instantiation of the essence knowledge. But how, on this basis, could we ever establish that we had indeed grasped this essence, and that this is indeed the appropriate essence? Surely, through some third-level act of reflection on this second-level act. We expound from an ontological point of view Ingarden's idea as to how this regress can be avoided

Zrozumieć klienta pomocy społecznej

tekst zamieszczony w czasopiśmie "Praca społeczna", listopad-grudzień 2008

Sensitivity of the photo-physical properties of organometallic complexes to small chemical changes

We investigate an effective model Hamiltonian for organometallic complexes that are widely used in optoelectronic devices. The two most important parameters in the model are $J$, the effective exchange interaction between the $\pi$ and $\pi^*$ orbitals of the ligands, and $\epsilon^*$, the renormalized energy gap between the highest occupied orbitals on the metal and on the ligand. We find that the degree of metal-to-ligand charge transfer (MLCT) character of the lowest triplet state is strongly dependent on the ratio $\epsilon^*/J$. $\epsilon^*$ is purely a property of the complex and can be changed significantly by even small variations in the complex's chemistry, such as replacing substituents on the ligands. We find that that small changes in $\epsilon^*/J$ can cause large changes in the properties of the complex, including the lifetime of the triplet state and the probability of injected charges (electrons and holes) forming triplet excitations. These results give some insight into the observed large changes in the photophysical properties of organometallic complexes caused by small changes in the ligands.Comment: Accepted for publication in J. Chem. Phys. 14 pages, 9 figures, Supplementary Info: 15 pages, 17 figure