Femtochemistry

Femtochemistry is the science that studies chemical reactions on extremely short timescales, approximately 10^–15 seconds (one femtosecond, hence the name).

Introduction

The steps in the formation of new products by chemical reactions take place in the femtosecond timescale and sometimes in attosecond timescales.^[1]

Nobel Prize winner

In 1999, Ahmed H. Zewail received the Nobel Prize in Chemistry for his pioneering work in this field. Zewail’s technique uses flashes of laser light that last for a few femtoseconds. Femtochemistry is the area of physical chemistry that addresses the short time period in which chemical reactions take place and investigates why some reactions occur but not others. Zewail’s picture-taking technique made possible these investigations. One of the first major discoveries of femtochemistry was to reveal details about the intermediate products that form during chemical reactions, which cannot be deduced from observing the starting and end products. Many publications have discussed the possibility of controlling chemical reactions by this method, but this remains controversial. ^{[citation needed]}

Pump–probe spectroscopy

The simplest approach and still one of the most common techniques is known as pump–probe spectroscopy. In this method, two or more optical pulses with variable time delay between them are used to investigate the processes happening during a chemical reaction. The first pulse (pump) initiates the reaction, by breaking a bond or exciting one of the reactants. The second pulse (probe) is then used to interrogate the progress of the reaction a certain period of time after initiation. As the reaction progresses, the response of the reacting system to the probe pulse will change. By continually scanning the time delay between pump and probe pulses and observing the response, workers can follow the progress of the reaction in real time.

References

^ Kling, Matthias F. (1 May 2008). "Attosecond Electron Dynamics". Annual Review of Physical Chemistry. 59 (1): 463–492. doi:10.1146/annurev.physchem.59.032607.093532. Retrieved 31 October 2011. {{cite journal}}: Check date values in: |year= and |year= / |date= mismatch (help); Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)

External links

The 1999 Nobel Prize in Chemistry, article on nobelprize.org
Controlling and probing atoms and molecules with ultrafast laser pulses, PhD Thesis

This chemistry-related article is a stub. You can help Wikipedia by expanding it.

[KlingVrakking-1] Kling, Matthias F. (1 May 2008). "Attosecond Electron Dynamics". Annual Review of Physical Chemistry. 59 (1): 463–492. doi:10.1146/annurev.physchem.59.032607.093532. Retrieved 31 October 2011. {{cite journal}}: Check date values in: |year= and |year= / |date= mismatch (help); Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)

[1]