Mostafa El-Sayed - AbsoluteAstronomy.com

Mostafa A. El-Sayed (born 8 May 1933 - Zifta

Zifta

Zifta: is an Egyptian town in the Nile delta, belongs to Gharbia governorate. It is across the nile from Mit Ghamr city of Ad Daqahliyah governorate.-History:...

, Egypt) is an Egyptian

Egyptians

Egyptians are nation an ethnic group made up of Mediterranean North Africans, the indigenous people of Egypt.Egyptian identity is closely tied to geography. The population of Egypt is concentrated in the lower Nile Valley, the small strip of cultivable land stretching from the First Cataract to...

-American

Egyptian American

Egyptian Americans are Americans of Egyptian ancestry, first-generation Egyptian immigrants, or descendants of Egyptians who immigrated to the United States. In the 2007 U.S. census, the number of people with Egyptian ancestry was estimated at 195,000, although some estimates range from several...

chemical physicist, a leading nanoscience researcher, a member of the National Academy of Sciences

United States National Academy of Sciences

The National Academy of Sciences is a corporation in the United States whose members serve pro bono as "advisers to the nation on science, engineering, and medicine." As a national academy, new members of the organization are elected annually by current members, based on their distinguished and...

and a US National Medal of Science

National Medal of Science

The National Medal of Science is an honor bestowed by the President of the United States to individuals in science and engineering who have made important contributions to the advancement of knowledge in the fields of behavioral and social sciences, biology, chemistry, engineering, mathematics and...

laureate. He is also known for the spectroscopy rule named after him, the El-Sayed rule.

Academic career

He earned his B.Sc.

Bachelor of Science

A Bachelor of Science is an undergraduate academic degree awarded for completed courses that generally last three to five years .-Australia:In Australia, the BSc is a 3 year degree, offered from 1st year on...

from Ain Shams University

Ain Shams University

Ain Shams University is an institute of higher education located in Cairo, Egypt. Founded in 1950, the university provides education at the undergraduate, graduate and post-graduate levels.-History:...

Faculty of Science in the 1953. El-Sayed earned his doctoral degree from Florida State University

Florida State University

The Florida State University is a space-grant and sea-grant public university located in Tallahassee, Florida, United States. It is a comprehensive doctoral research university with medical programs and significant research activity as determined by the Carnegie Foundation...

working with Michael Kasha

Michael Kasha

Michael Kasha is an American physical chemist and molecular spectroscopist who is one of the original founders of the Institute of Molecular Biophysics at Florida State University . Born in Elizabeth, NJ to a family of Ukrainian immigrants, he earned his Ph.D...

, the last student of the legendary G. N. Lewis . He spent time as a researcher at Harvard University

Harvard University

Harvard University is a private Ivy League university located in Cambridge, Massachusetts, United States, established in 1636 by the Massachusetts legislature. Harvard is the oldest institution of higher learning in the United States and the first corporation chartered in the country...

, Yale University

Yale University

Yale University is a private, Ivy League university located in New Haven, Connecticut, United States. Founded in 1701 in the Colony of Connecticut, the university is the third-oldest institution of higher education in the United States...

and the California Institute of Technology

California Institute of Technology

The California Institute of Technology is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering...

before joining the faculty of the University of California at Los Angeles in 1961. He is currently the Julius Brown Chair and Regents Professor of Chemistry and Biochemistry at the Georgia Institute of Technology

Georgia Institute of Technology

The Georgia Institute of Technology is a public research university in Atlanta, Georgia, in the United States...

. He heads the Laser Dynamics Lab there.

El-Sayed is a former editor-in-chief of the Journal of Physical Chemistry.

Research

El-Sayed and his research

Research

Research can be defined as the scientific search for knowledge, or as any systematic investigation, to establish novel facts, solve new or existing problems, prove new ideas, or develop new theories, usually using a scientific method...

group has contributed to many important areas of physical and materials chemistry research. El-Sayed's research interests include the use of steady-state and ultra fast laser spectroscopy

Ultra fast laser spectroscopy

Ultra-fast laser spectroscopy is the study of molecules on extremely short time scales after their excitation with a pulsed laser. This method is used extensively to examine the energy states and electron dynamics of any molecule whose reaction to light is of interest...

to understand relaxation, transport and conversion of energy in molecules, in solids, in photosynthetic systems, semiconductor quantum dots and metal nanostructures. The El-Sayed group has also been involved in the development of new techniques such as magnetophoto selection, picosecond Raman spectroscopy

Raman spectroscopy

Raman spectroscopy is a spectroscopic technique used to study vibrational, rotational, and other low-frequency modes in a system.It relies on inelastic scattering, or Raman scattering, of monochromatic light, usually from a laser in the visible, near infrared, or near ultraviolet range...

and phosphorescence microwave double resonance spectroscopy. A major focus of his lab is currently on the optical and chemical properties of noble metal

Noble metal

Noble metals are metals that are resistant to corrosion and oxidation in moist air, unlike most base metals. They tend to be precious, often due to their rarity in the Earth's crust...

nanoparticles and their applications in nanocatalysis

Catalysis

Catalysis is the change in rate of a chemical reaction due to the participation of a substance called a catalyst. Unlike other reagents that participate in the chemical reaction, a catalyst is not consumed by the reaction itself. A catalyst may participate in multiple chemical transformations....

, nanophotonics

Nanophotonics

Nanophotonics or Nano-optics is the study of the behavior of light on the nanometer scale. It is considered as a branch of optical engineering which deals with optics, or the interaction of light with particles or substances, at deeply subwavelength length scales...

and nanomedicine

Nanomedicine

Nanomedicine is the medical application of nanotechnology. Nanomedicine ranges from the medical applications of nanomaterials, to nanoelectronic biosensors, and even possible future applications of molecular nanotechnology. Current problems for nanomedicine involve understanding the issues related...

. His lab is known for the development of the gold nanorod

Nanorod

In nanotechnology, nanorods are one morphology of nanoscale objects. Each of their dimensions range from 1–100 nm. They may be synthesized from metals or semiconducting materials. Standard aspect ratios are 3-5. Nanorods are produced by direct chemical synthesis...

technology. Professor El-Sayed has over 500 publications in refereed journals in the areas of spectroscopy

Spectroscopy

Spectroscopy is the study of the interaction between matter and radiated energy. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, e.g., by a prism. Later the concept was expanded greatly to comprise any interaction with radiative...

, molecular dynamics

Molecular dynamics

Molecular dynamics is a computer simulation of physical movements of atoms and molecules. The atoms and molecules are allowed to interact for a period of time, giving a view of the motion of the atoms...

and nanoscience. Prof. El-Sayed has supervised the research of over 70 PhD students, 35 postdoctoral fellows and 20 visiting professors, several of whom hold key positions in the scientific community.

Dr. Mostafa El Sayed's son, Dr. Ivan El-Sayed, the Professor of Tumour Surgery at the University of California

University of California

The University of California is a public university system in the U.S. state of California. Under the California Master Plan for Higher Education, the University of California is a part of the state's three-tier public higher education system, which also includes the California State University...

, took part in applying these outcomes on cancerous cells of some animals.

Honors

For his work in the area of applying laser

Laser

A laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation...

spectroscopic techniques to study of properties and behavior on the nanoscale, El-Sayed was elected to the National Academy of Sciences

United States National Academy of Sciences

in 1980, and in 2002, he won the Irving Langmuir Award

Irving Langmuir Award

The Irving Langmuir Award in Chemical Physics is awarded annually, in even years by the American Chemical Society and in odd years by the American Physical Society. The award is meant to recognize and encourage outstanding interdisciplinary research in chemistry and physics, in the spirit of Irving...

in Chemical Physics. He has been the recipient of the 1990 King Faisal International Prize ("Arabian Nobel Prize") in Sciences, Georgia Tech's highest award, "The Class of 1943 Distinguished Professor", an honorary doctorate of philosophy from the Hebrew University, and several other awards including some from the different American Chemical Society

American Chemical Society

The American Chemical Society is a scientific society based in the United States that supports scientific inquiry in the field of chemistry. Founded in 1876 at New York University, the ACS currently has more than 161,000 members at all degree-levels and in all fields of chemistry, chemical...

local sections. He was a Sherman Fairchild

Sherman Fairchild

Sherman Mills Fairchild was an inventor and serial entrepreneur who founded over 70 companies namely Fairchild Aircraft, Fairchild Industries, Fairchild Aviation Corporation and Fairchild Camera and Instrument. Fairchild made significant contributions to the aviation industry and was inducted into...

Distinguished Scholar at the California Institute of Technology

California Institute of Technology

and an Alexander von Humboldt Senior U.S. Scientist Awardee. He served as editor-in-chief of the Journal of Physical Chemistry from 1980–2004 and has also served as the U.S. editor of the International Reviews in Physical Chemistry. He is a Fellow of the American Academy of Arts and Sciences

American Academy of Arts and Sciences

The American Academy of Arts and Sciences is an independent policy research center that conducts multidisciplinary studies of complex and emerging problems. The Academy’s elected members are leaders in the academic disciplines, the arts, business, and public affairs.James Bowdoin, John Adams, and...

, a member of the American Physical Society

American Physical Society

The American Physical Society is the world's second largest organization of physicists, behind the Deutsche Physikalische Gesellschaft. The Society publishes more than a dozen scientific journals, including the world renowned Physical Review and Physical Review Letters, and organizes more than 20...

, the American Association for the Advancement of Science

American Association for the Advancement of Science

The American Association for the Advancement of Science is an international non-profit organization with the stated goals of promoting cooperation among scientists, defending scientific freedom, encouraging scientific responsibility, and supporting scientific education and science outreach for the...

and the Third World Academy of Science. Mostafa El-Sayed was awarded the 2007 US National Medal of Science

National Medal of Science

"for his seminal and creative contributions to our understanding of the electronic

Electricity

Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire...

and optical properties of nanomaterials

Nanomaterials

Nanomaterials is a field that takes a materials science-based approach to nanotechnology. It studies materials with morphological features on the nanoscale, and especially those that have special properties stemming from their nanoscale dimensions...

and to their applications in nanocatalysis

Catalysis

and nanomedicine

Nanomedicine

, for his humanitarian efforts of exchange among countries and for his role in developing the scientific leadership of tomorrow." Dr. Mostafa was also announced to be the recipient of the 2009 Ahmed Zewail

Ahmed Zewail

Ahmed Hassan Zewail is an Egyptian-American scientist who won the 1999 Nobel Prize in Chemistry for his work on femtochemistry. He is the Linus Pauling Chair Professor Chemistry and Professor of Physics at the California Institute of Technology.- Birth and education :Ahmed Zewail was born on...

prize in molecular sciences.

El-Sayed's rule

Intersystem Crossing

Intersystem crossing

Intersystem crossing is a radiationless process involving a transition between two electronic states with different spin multiplicity.-Singlet and triplet states:...

(ISC) is a photophysical process involving an isoenergetic radiationless transition between two electronic state

Electronic state

Electronic state is a quantum state of a system consisting of electrons . The state with lowest energy is called ground state, states with higher energy are excited states.See Energy level....

s having different multiplicities. It often results in a vibrationally excited molecular entity in the lower electronic state, which then usually decays to its lowest molecular vibration

Molecular vibration

A molecular vibration occurs when atoms in a molecule are in periodic motion while the molecule as a whole has constant translational and rotational motion...

al level. ISC is forbidden by rules of conservation of angular momentum

Angular momentum

In physics, angular momentum, moment of momentum, or rotational momentum is a conserved vector quantity that can be used to describe the overall state of a physical system...

. As a consequence, ISC generally occurs on very long time scales. However the El-Sayed’s rule states that the rate of intersystem crossing, e.g. from the lowest singlet state to the triplet manifold, is relatively large if the radiationless transition involves a change of molecular orbital

Molecular orbital

In chemistry, a molecular orbital is a mathematical function describing the wave-like behavior of an electron in a molecule. This function can be used to calculate chemical and physical properties such as the probability of finding an electron in any specific region. The term "orbital" was first...

type. For example a (π,π*) singlet could transition to a (n,π*) triplet state

Triplet state

A spin triplet is a set of three quantum states of a system, each with total spin S = 1 . The system could consist of a single elementary massive spin 1 particle such as a W or Z boson, or be some multiparticle state with total spin angular momentum of one.In physics, spin is the angular momentum...

, but not to a (π,π*) triplet state and vice versa. Formulated by Prof. Mostafa. A. El-Sayed in 1960s, this rule found in most photochemistry

Photochemistry

Photochemistry, a sub-discipline of chemistry, is the study of chemical reactions that proceed with the absorption of light by atoms or molecules.. Everyday examples include photosynthesis, the degradation of plastics and the formation of vitamin D with sunlight.-Principles:Light is a type of...

textbooks is useful in understanding phosphorescence

Phosphorescence

Phosphorescence is a specific type of photoluminescence related to fluorescence. Unlike fluorescence, a phosphorescent material does not immediately re-emit the radiation it absorbs. The slower time scales of the re-emission are associated with "forbidden" energy state transitions in quantum...

, vibrational relaxation, intersystem crossing

Intersystem crossing

Intersystem crossing is a radiationless process involving a transition between two electronic states with different spin multiplicity.-Singlet and triplet states:...

, internal conversion

Internal conversion

Internal conversion is a radioactive decay process where an excited nucleus interacts with an electron in one of the lower atomic orbitals, causing the electron to be emitted from the atom. Thus, in an internal conversion process, a high-energy electron is emitted from the radioactive atom, but...

and lifetimes of excited states in molecules.

External links

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