Femtochemistry is the science that studies chemical reactions on extremely short timescales, approximately 10^–15 seconds (this is one femtosecond, hence the name). Science (from the Latin scientia, meaning " Knowledge " or "knowing" is the effort to discover, and increase human understanding A chemical reaction is a process that always results in the interconversion of Chemical substances The substance or substances initially involved in a chemical reaction are called To help compare Orders of magnitude of different Times this page lists times between 10&minus15 second and 10&minus12 second (1 Femto To help compare Orders of magnitude of different Times this page lists times between 10&minus15 second and 10&minus12 second (1 Femto

In 1999, Ahmed H. Zewail received the Nobel Prize in Chemistry for his pioneering work in this field. Year 1999 ( MCMXCIX) was a Common year starting on Friday (link will display full 1999 Gregorian calendar) Ahmed Hassan Zewail (أحمد حسن زويل (born February 26 1946 in Damanhur, Egypt) is an Egyptian American scientist and the The Nobel Prize in Chemistry (Nobelpriset i kemi is awarded annually by the Royal Swedish Academy of Sciences to scientists in the various fields of Chemistry.

Zewail’s technique uses flashes of laser light that last for a few femtoseconds. A laser is a device that emits Light ( Electromagnetic radiation) through a process called Stimulated emission. 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. Physical chemistry, is the application of Physics to macroscopic microscopic atomic subatomic and particulate phenomena in chemical systems It is mostly defined as a large 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.

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.

External links

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

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