Chemical Physics and Physical Chemistry

Joseph Falke, University of Colorado; Physical Seminar

Thu, 2013-10-03 13:00 - 14:30
Location: 

Lych Lecture Hall, Chemistry Department

Greg Scholes, University of Toronto; Physical Chemistry Seminar

Thu, 2013-06-27 13:00
Speaker: 

Prof. Gregory Scholes

University of Toronto

 

Functional novelties employed in light harvesting by diverse photosynthetic systems

 

Abstract:

 

Photosynthetic light harvesting complexes are sophisticated multichromophoric assemblies used to regulate and concentrate photo-excitations for delivery to reaction centers under wide-ranging incident irradiances [1]. They provide wonderful model systems for the study of energy transfer mechanisms in well-defined structures [2]. I will describe a few examples of ultrafast energy transfer in photosynthetic light harvesting, including the incredible use of nominally dark higher excited states of carotenoids to distribute excitation energy in LH2 from purple bacteria [3]. I will address the current status and issues regarding coherent ultrafast energy transfer in light harvesting complexes of cryptophyte algae.

 

[1] G. D. Scholes, T. Mirkovic, D. B. Turner, F. Fassioli and A. Buchleitner “Solar light harvesting by energy transfer: From ecology to quantum mechanics” Energy Environ. Sci. 5, 9374–9393 (2012).

[2] G. D. Scholes, G. R. Fleming, A. Olaya-Castro and R. van Grondelle, “Lessons from nature about solar light harvesting” Nature Chem. 3, 763–774 (2011).

[3] E. E. Ostroumov, R. M. Mulvaney, R. J. Cogdell, G. D. Scholes, “Broadband 2D Spectroscopy Reveals a Carotenoid Dark State in Purple Bacteria”, Science 340, 52–56 (2013).

Location: 

Lynch Lecture Hall

Special Seminar: David Sivak, UCSF

Mon, 2013-02-18 10:00
Speaker: 

Dr. David Sivak

University of California, San Francisco

 

Nonequilibrium Thermodynamics: Free Energy, Optimal Control, and Optimal Response

 

Abstract: Molecular machines are protein complexes that convert between different forms of energy, and they feature prominently in essentially any major cell biological process. A plausible hypothesis holds that evolution has sculpted these machines to efficiently transmit energy and information in their natural contexts, where energetic fluctuations are large and nonequilibrium driving forces are strong. Toward a systematic picture of efficient, stochastic, nonequilibrium energy and information transmission, I present theoretical developments in three distinct yet related areas of nonequilibrium statistical mechanics: How can we measure how far from equilibrium a driven system is? How do we find efficient methods to push a system rapidly from one state to another? And finally, what are generic properties of systems that efficiently harness the energy and information present in environmental fluctuations?

Location: 

Lynch Lecture Hall

Hirschmann Visiting Professor Lecture 3 - James Skinner, Univ. Wisconsin

Thu, 2013-02-21 13:00
Speaker: 

James L. Skinner, University of Wisconsin, Madison

 

Lecture 3

Protein structure and vibrational spectroscopy
Thursday, February 21, 2013
1:00 PM

Location: 

Lynch Lecture Hall

Hirschmann Visiting Professor Lecture 2 - James Skinner, Univ. Wisconsin

Wed, 2013-02-20 16:00
Speaker: 

James L. Skinner, University of Wisconsin, Madison

 


Lecture 2

Water at liquid/vapor, surfactant, and lipid interfaces
Wednesday, February 20, 2013
4:00 PM

 

PLEASE NOTE NEW TIME.

Location: 

Lynch Lecture Hall

Special Seminar: Erol Akçay, Princeton

Mon, 2013-02-04 10:00
Speaker: 
Dr. Erol Akçay
Princeton University

New frontiers in social evolution theory

Host: Josh Plotkin (Biology)
Location: 

Lynch Lecture Hall

 

Cooperation between organisms is a major driving force of biological organization at all levels, from single cells to whole ecosystems. Understanding the evolutionary dynamics of cooperation and other social traits therefore is a central goal of evolutionary theory. I will talk about my recent work that aims to advance the frontiers of social evolution theory in two directions.

 

Special Seminar: Emilia Huerta-Sanchez, University of California, Berkeley

Mon, 2013-01-28 10:00
Speaker: 

Dr. Emilia Huerta-Sanchez

University of California, Berkeley

 

Detecting and characterizing natural selection from next generation sequencing data

 

Host: Charles Epstein (Math)

Location: 

Lynch Lecture Hall

 

Special Seminar: Sharon Aviran, University of California, Berkeley

Thu, 2013-01-24 10:00
Speaker: 

Dr. Sharon Aviran

University of California, Berkeley

 

High-throughput RNA structure analysis from chemical footprinting experiments

 

Host: Randy Kamien (Physics)

Location: 

Lynch Lecture Hall

 

New regulatory roles continue to emerge for both natural and engineered RNAs, many of which have specific structures essential to their function. This highlights a growing need to develop technologies that enable rapid and accurate characterization of structural features within complex RNA populations. Yet, available techniques that are reliable are also vastly limited by technological constraints, while the accuracy of popular computational methods is generally poor. These limitations thus pose a major barrier to comprehensive determination of structure from sequence.

Department of Chemistry

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