Real-time observation of bond formation by using Femtosecond
X-ray liquidography (solution scattering)
February 18, 2015
The
research team of the Center for Nanomaterials and Chemical Reactions at the
Institute for Basic Science (IBS) has successfully visualized the entire
process of bond formation in solution by using femtosecond time-resolved X-ray liquidography
(femtosecond TRXL) for the first time in the world.
Every
researcher’s longstanding dream to observe real-time bond formation in chemical
reactions has come true. Since this formation takes less than one picosecond, researchers
have not been able to visualize the birth of molecules.
The
research team has used femtosecond TRXL in order to visualize the formation of
a gold trimer complex in real time without being limited by slow diffusion.
They
have focused on the process of photoinduced bond formation between gold (Au) atoms
dissolved in water. In the ground (S0) state, Au atoms are weakly
bound to each other in a bent geometry by van der Waals interactions. On
photoexcitation, the S0 state rapidly converts into an excited (S1)
state, leading to the formation of covalent Au-Au bonds and bent-to-linear
transition. Then, the S1 state changes to a triplet (T1) state
with a time constant of 1.6 picosecond, accompanying further bond contraction
by 0.1 Å. Later, the T1 state of the trimer transforms to a tetramer
on nanosecond time scale, and Au atoms return to their original bent structure.
“By
using femtosecond TRXL, we will be able to observe molecular vibration and rotation
in the solution phase in real time,” says Hyotcherl Ihee, the group leader of
the Center for Nanomaterials at IBS, as well as the professor of the Department
of Chemistry at Korea Advanced Institute of Science and Technology.
###
Notes for editors
-
References
Kyung Hwan Kim, Jong Goo Kim, Shunsuke
Nozawa, Tokushi Sato, Key Young Oang, Tae Wu Kim, Hosung Ki, Junbeom Jo,
Sungjun Park, Changyong Song, Takahiro Sato, Kanade Ogawa, Tadashi Togashi,
Kensuke Tono, Makina Yabashi, Tetsuya Ishikawa, Joonghan Kim, Ryong Ryoo,
Jeongho Kim, Hyotcherl Ihee & Shin-ichi Adachi(2015). Direct observation of
bond formation in solution with femtosecond X-ray scattering. Nature. Published
online. DOI: 10.1038/nature14163 (http://www.nature.com/nature/journal/v518/n7539/full/nature14163.html)
-
For Media Contact
Mr.
Shi Bo Shim, Head of Department of Communications, Institute for Basic Science (+82-42-878-8189;
sibo@ibs.re.kr)
or Ms. Sunny Kim, Department of Communications, Institute for Basic Science (+82-42-878-8135;
Sunnykim@ibs.re.kr)
-
About Institute for
Basic Science (IBS)
The IBS was founded in 2011 by the government of the Republic of Korea. With
the sole purpose of driving forward the development of basic science in Korea,
IBS will be comprised of a total of 50 research centers in all fields of basic
science, including mathematics, physics, chemistry, life science, earth science
and interdisciplinary science. IBS has launched 24 research centers as of January
2015. There is one mathematics, eight physics, six chemistry, seven life
science, and two interdisciplinary research centers.
|