A study of the low-lying singlet and triplet electronic states of chlorophyll A and B

Chlorophylls have been extensively investigated both experimentally and theoretically owing to the fact that they are essential for photosynthesis. We have studied two forms of chlorophyll, chlorophyll a and chlorophyll b, by means of density functional theory. Optimization of S0, S1 and T1 states was performed with the B3-LYP functional. The computed fluorescence lifetimes show good agreement with the available experimental data. The electronic adiabatic energies of S1 and T1 states are 2.09/2.12 and 1.19/1.29 eV for chlorophyll a and chlorophyll b respectively. We discussed the implications of this results on the triplet formation. Also, the calculated vertical ionization potentials shows good agreement with the experimental results. [Projekat Ministarstva nauke Reoublike Srbije, br. 172040

Interpretation of some bilateral treaties by the International Court of Justice

The text analyzes interpretations of bilateral treaties in three cases decided by the International Court of Justice in the period of 2009 to 2011. As the interpretation of the treaties was performed by applying the same rules laid down in Article 31 and 32 of the Vienna Convention on the Law of Treaties, it includes the same or similar factors and methods. Specific characteristics of each case, in particular the specific characteristics of treaties, resulted in certain differences. The range of factors used in interpretation of a treaty governing a unique issue and the range of factors used in interpretation of a treaty whose object belongs to the class of objects of an area of international law are not the same

Means of interpretation of international treaties and determinants of their significance

The choice of means of interpretation and attribution appropriate weight to them may well determine the outcome of an interpretation. Articles 31 of the 32 of the VCLT leave broad discretion to an interpreter in that respect. That may turn an interpretation into a legal process of diminishing predictability and undermine legal certainty. Judicious discretion in the choice and weighing means of interpretation should not be unlimited. The nature and particular characteristics of a treaty, of a question that should be answered by interpretation, and of the means of interpretation, might have the role of determinants of the significance of means of interpretation. The correlations in a triangle of the particular characteristics of the treaty, the question and the means of interpretation, established as typical in the practice of international courts, might constitute a standard model of interpretation. An international court would be expected to explain its departure from the model

The interrelationship between the European Convention on Human Rights and the Aarhus Convention

The Taşkın case manifests mutual supportiveness of the Aarhus Convention and the European Convention on Human Rights as well as of the general international environmental and the right to private and family life. Interactions between the protection of the environment and human rights are complex and involve economic and political factors. Legal concepts of sustainable development, mutual supportiveness and balance of interests bring new principles governing the complex interactions. They are reflected in Taşkın

Tuning charge transfer states in the G-octet-metal ion complexes for the potential nanotechnological applications

Here we study G-octet-metal ion complexes (M-G8) which act as models for the G-quadruplex supramolecular arrangement within DNA. We used DFT based molecular dynamics (BLYP-D3/DZVP+PW+GTH) for the configuration sampling purposes and calculated electronic excitations to initially populated (Franck-Condon) states. We use descriptors based on one-electron transition density matrix to seize charge transfer content of the selected excited states. We use TDDFT formalism (CAM-B3LYP/6-31G(d)) to calculate one-electron transition density matrices and absorption spectrum

Influence of the metal ions on the charge transfer states in the G-octet-metal ion complexes

In this work, we study G-octet-metal ion complexes which act as models for the G-quadruplex supramolecular arrangement within DNA. We used DFT based molecular dynamics (BLYP-D3/DZVP+PW+GTH) for configuration sampling purposes and calculated electronic excitations to initially populated (Franck-Condon) states. To capture charge transfer content of the excited states, we used descriptors who rely on the analysis of the one-electron transition density matrix acquired from the TDDFT calculation (CAM-B3LYP/6-31G(d))

Stabilities of nanohydrated thymine radical cations: insights from multiphoton ionization experiments and ab initio calculations

Multi-photon ionization experiments have been carried out on thymine-water clusters in the gas phase. Metastable H2O loss from T+(H2O)n was observed at n ≥ 3 only. Ab initio quantum-chemical calculations of a large range of optimized T+(H2O)n conformers have been performed up to n = 4, enabling binding energies of water to be derived. These decrease smoothly with n, consistent with the general trend of increasing metastable H2O loss in the experimental data. The lowest-energy conformers of T+(H2O)3 and T+(H2O)4 feature intermolecular bonding via charge-dipole interactions, in contrast with the purely hydrogen-bonded neutrals. We found no evidence for a closed hydration shell at n = 4, also contrasting with studies of neutral clusters