Ultrafast potential energy surface softening of one-dimensional organic conductors revealed by picosecond time-resolved Laue crystallography.
Time-resolved Laue crystallography has been employed to study the structural dynamics of a one-dimensional organic conductor (tetrathiafulvalene-p-chloranil) during photoexcitation in the regime of the neutral to ionic phase transition. Exciting this crystalline system with 800 nm 100 fs long optical pulses leads to ultrafast population of a structural intermediate as early as 50 ps after excitation with a lifetime of at least 10 ns. Starting from the neutral phase, this intermediate has been assigned as a precursor state toward the photoinduced population of the ionic phase. The observed intensity changes are significantly different from comparable equilibrium structures. The interpretation of this structural data is that the potential of this intermediate is being softened during its population in a dynamical process. The depopulation proceeds through thermal processes.
Messerschmidt
Marc
M
SLAC, Menlo Park, California 94025, USA. mcmesser@slac.stanford.edu
Tschentscher
Thomas
T
Cammarata
Marco
M
Meents
Alke
A
Sager
Christian
C
Davaasambuu
Jav
J
Busse
Gerhard
G
Techert
Simone
S
D002703:Chloranil / Q000031:analogs & derivatives* / Q000737:chemistry*; D003461:Crystallography / Q000379:methods*; D004553:Electric Conductivity; D004583:Electrons; D004735:Energy Transfer; D010777:Photochemistry; D011522:Protons; D013499:Surface Properties; D013997:Time Factors
D011522:Protons; C557992:tetrathiafulvalene-p-chloranil; D002703:Chloranil