Amir Wand 2011-2012

Institution of PhD:
Hebrew University of Jerusalem
Academic Discipline of PhD:
Physical Chemistry
PhD Advisor/s:
Prof. Sanford (Sandy) Ruhman
Dissertation Topic:
Investigation of Photobiology with Advanced Ultrafast Spectroscopy
Year Awarded PhD:
Present Institution:
Nova Measuring Instruments
Links to Recent Publications:
Publication 1
Publication 3
Publication 5
Publication 7
Publication 9
Publication 9

Amir Wand is a chemist who has recently completed his PhD in The Hebrew University of Jerusalem under the supervision of Prof. Sandy Ruhman. His PhD thesis “An Investigation of Photobiology with Advanced Ultrafast Spectroscopy” was written in the Institute of Chemistry within Prof. Ruhman’s group,  utilizing ultrafast spectroscopy techniques to study femtochemistry – the study of chemical reactions on extremely short timescales, as they take place. To that end, a “camera” which is as fast – or faster – than typical molecular movements is necessary, which take place on a femtosecond timescale (1 femtosecond=10^-15 second, one millionth of one billionth of a second !). This is achieved using state-of-the-art home-built laser systems, which produce laser pulses of such ultrashort duration. By “clocking” chemical reactions, his group’s ultimate goal is the construction of multidimensional reaction coordinates, which will lead to a comprehensive description of reaction mechanisms and pathways – the “holy grail” of wet chemical physics.

Amir’s research during both his MSc and PhD studies focused on the implementation of advanced ultrafast spectroscopy techniques to the study of photoinduced physicochemical processes – in particular for photo-biological systems such as the retinal proteins. These proteins are responsible for conversion of solar (sun) energy to utilizable chemical energy, used for a variety of biological functions in all kingdoms of life (from archaea and bacteria to mammals). In them all, the biological function is triggered by absorption of a photon, which initiates the reactivity. Though biological activity is usually achieved only milliseconds or longer after excitation, the primary photochemical events – which are finished already within hundreds of femtoseconds to a few picoseconds – define the total quantum yield of the protein functionality (as high as 70%!), thus making them the crucial steps in the cycle and vital for understanding the efficient energy conversion and storing mechanisms.

During his PhD studies, Amir focused on:

(a) Mapping photochemistry of newly-discovered retinal proteins (e.g. Anabaena sensory rhodopsin), or of new aspects/spectral regions of well-known members (such as bacteriorhodopsin).

(b) Development of ultrafast techniques for obtaining transient structural information (changes in structure and bonding), vital for understanding the underlying molecular dynamics.

His findings have been published in a series of papers in peer-reviewed journals, among them Physical Chemistry Chemical Physics, Annual Review of Physical Chemistry and  Journal of  Physical Chemistry.