Advanced Ceramics, traditionally a choice for structural applications, has recently displayed properties for a variety of functional applications ranging from thermal imaging to thermal barrier coatings. Poly crystalline ceramics, when hundred percent dense can be transparent to electromagnetic radiations in the wavelength region of 0.4 to 10 microns. The transparency in visible and infra red regions renders them serviceable for applications such as thermal imaging, optical lighting and aesthetic dental ceramics. Alternatively, rare earth phosphates like lanthanum phosphate by virtue of their low thermal conductivity values can function as thermal barrier coatings. The non reactivity towards molten metals, including that of radioactive ones, make them a potential candidate for lubricious coatings at high temperatures. The photocatalytic property of titania is widely explored for self cleaning and antimicrobial applications on a variety of substrates. The presentation summarises the material processing efforts made in these regards to develop competent technologies indigenously.
The chemical bonds break, form, or geometrically change with amazing rapidity during the transformation of reactants to products. This ultrafast transformation is a dynamic process involving the mechanical motion of electrons and atomic nuclei. As the speed of atomic motion is ~1 km/second, the average time required to experiment atomic-scale dynamics over a distance of an angstrom is ~100 femtoseconds. Hence the advantage of using ultrashort pulses is that they open the door to investigate the dynamics of the system directly, i.e., the movement of individual particles such as electrons or atoms. The key is that the duration of the laser pulses must be shorter than the time scale of the dynamics that one wants to observe.
In this presentation, I will start with the history, fundamental and construction of lasers. Explaining about the various techniques involved in the ultrafast spectroscopy and their advantages. The application of ultrafast spectroscopy directly into the general fields of chemistry, biology and materials will be demonstrated with physics background. For examples, the ultrafast vibrational motion of the heme in the CO-sensing transcriptional activator protein, CooA (Biology) and ultrafast processes involved in the dye sensitized solar cell function (Material) will be discussed.
Quantum-mechanical (QM) techniques such as density-functional-theory calculations and ab initio computational methods provide accurate modelling of chemical reactions and accurate prediction of the properties of chemicals. QM techniques have become affordable to chemists as the economics of high performance computing have become impressive: the cost of 1 gigaflops of computing power in the 1960s was about US$7.9 trillion in today’s currency, whereas the same computing power is available now for less than 20 cents (http://news.bbc.co.uk/2/hi/technology/4554025.stm). In this scenario, chemists are encouraged to practice rational design based on computational simulation rather than waiting for discovery to happen through serendipity or trial and error. In this talk, some of our recent computational experiments will be presented which will show that by careful analysis of electronic structure and bonding, realistic predictions on functional molecules can be made. Mainly the discovery of a new type of bonding in organometallic chemistry will be discussed along with its application in designing new CC bond metathesis catalysts and functional molecules.