Project coordinator: Prof. Ana Proykova (anap<at>phys.uni-sofia.bg)
Technical assistant: Borislava Kenarova (borislava.kenarova<at>gmail.com)
Telephone: (+359 2) 8161-828
Faculty of Physics, Atomic Physics Department, room V25
5 James Bourchier blvd, Sofia, BG-1164, Bulgaria
The Integrated Research Center on Computational Sciences in the Microworld (IRC-CoSiM) aims at bringing the Natural Sciences at the University of Sofia to the forefront of a new technological revolution driven by fundamental research and information technology. The revolution is rooted in advances in engineering nano-scale materials and their usage in a variety of sytems which requires extreme integration of skills, knowledge accumulated in (sometimes) quite different fields.
Clustering is a general physical phenomenon manifesting itself at very different scales (levels) of matter organization or self-organization. A group of objects bound together by some interaction can be called a cluster. Such group of objects could be a group of nucleons in a nuclear matter, this can be a group of atoms, molecules or nanosize droplets stuck together on surface or this can be a group of galaxies in the Universe. Structure and properties of the cluster type of objects are predetermined by forces holding constituents together within a system. In spite of difference in the scale of cluster systems and in the types of forces holding them together, they sometime allow very straightforward analogies. For example, the liquid drop model can be successfully utilized for the explanation of nuclear fission and for the understanding of stability of charged nanoclusters. Cluster is a relevant concept for different fields of science. Clustering phenomenon is relevant for astrophysics, atomic and molecular physics, chemistry, molecular biology, solid-state physics, nuclear physics, plasma physics and technology (clustering in the wireless or computer networks).
In spite of that huge diversity of fields, are there some fundamental laws governing the behaviour and the properties of cluster systems at different scales?
We have identified a number of common open fundamental problems which can be addressed for the most of the mentioned systems in spite of differences in their genesis:
- What are the underlying principles of the self-organization and self-assembly of matter? How does a function emerge at the nano-scale and in mesoscopic systems?
- Are these principles classical or quantum?
- What are the criteria for the stability of complex mesoscopic and nano-systems?
- What are their characteristics, typical conformations and dynamical properties?
- How do the properties (electric, magnetic, optical, transport, thermodynamic, quantum, etc.) of mesoscopic and nano-systems come into play, and how do they change with variation of the system size?
- How are the properties of mesoscopic and nano-systems altered by an environment, such as a liquid medium, a solid substrate, a confining cage, a thin film or by an external electromagnetic field? (vii) how specific features of complex mesoscopic and nano-systems manifest themselves in physical, chemical and biological processes in which they are involved?
Some answers to these questions have been found. The researchers at the IRC-CoSiM will provide more answers and hopefully will ask new questions.