Speaker: Ms. Anjana Dutta
Negative Thermal Expansion
Date & Time: Thursday 7th September, 2017 at 4.00 PM
Venue: SSCU AUDITORIUM
Materials, which we encounter in everyday life, in general, expand on heating. This is to be expected because the interatomic distances between two bonded atoms increases with increasing temperature. However, there are some materials which exhibit negative thermal expansion (NTE) in specific temperature ranges. The origins for such an anomalous behaviour is related to several factors for example, shortening of bond lengths during phase transition, rigid unit modes, electronic transition, oxygen vacancy, magnetic effect. There are a number of important potential applications for substances with a negative coefficient of thermal expansion. I will discuss the origins of negative thermal expansion and tuning of thermal expansion coefficient with several examples.
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