Tetracene
Encyclopedia
Tetracene, also called naphthacene, is a polycyclic aromatic hydrocarbon
Polycyclic aromatic hydrocarbon
Polycyclic aromatic hydrocarbons , also known as poly-aromatic hydrocarbons or polynuclear aromatic hydrocarbons, are potent atmospheric pollutants that consist of fused aromatic rings and do not contain heteroatoms or carry substituents. Naphthalene is the simplest example of a PAH...

. It has the appearance of a pale orange powder. Tetracene is the four-ringed member of the series of acenes, the previous one being anthracene
Anthracene
Anthracene is a solid polycyclic aromatic hydrocarbon consisting of three fused benzene rings. It is a component of coal-tar. Anthracene is used in the production of the red dye alizarin and other dyes...

 (tricene) and the next one being pentacene
Pentacene
Pentacene is a polycyclic aromatic hydrocarbon consisting of five linearly-fused benzene rings. This highly conjugated compound is an organic semiconductor. The compound generates excitons upon absorption of ultra-violet or visible light; this makes it very sensitive to oxidation...

.

Tetracene is a molecular organic semiconductor
Organic semiconductor
An organic semiconductor is an organic material with semiconductor properties. Single molecules, short chain and organic polymers can be semiconductive. Semiconducting small molecules include the polycyclic aromatic compounds pentacene, anthracene, and rubrene...

, used in organic field-effect transistors (OFETs) and organic light-emitting diodes (OLEDs). In May 2007, researchers from two Japanese universities, Tohoku University
Tohoku University
, abbreviated to , located in the city of Sendai, Miyagi Prefecture in the Tōhoku Region, Japan, is a Japanese national university. It is the third oldest Imperial University in Japan and is a member of the National Seven Universities...

 in Sendai and Osaka University
Osaka University
, or , is a major national university located in Osaka, Japan. It is the sixth oldest university in Japan as the Osaka Prefectural Medical College, and formerly one of the Imperial Universities of Japan...

, have reported an ambipolar light-emitting transistor made of a single tetracene crystal. Ambipolar means that the electric charge
Electric charge
Electric charge is a physical property of matter that causes it to experience a force when near other electrically charged matter. Electric charge comes in two types, called positive and negative. Two positively charged substances, or objects, experience a mutual repulsive force, as do two...

 is transported by both, positively charged holes
Electron hole
An electron hole is the conceptual and mathematical opposite of an electron, useful in the study of physics, chemistry, and electrical engineering. The concept describes the lack of an electron at a position where one could exist in an atom or atomic lattice...

 and negatively charged electrons. Tetracene can be also used as a gain medium in dye lasers as a sensitiser in chemoluminescence
Chemoluminescence
Chemiluminescence is the emission of light with limited emission of heat , as the result of a chemical reaction...

.

Jan Hendrik Schön
Jan Hendrik Schön
The Schön scandal concerns German physicist Jan Hendrik Schön who briefly rose to prominence after a series of apparent breakthroughs with semiconductors that were later discovered to be fraudulent...

 during his time at Bell Labs
Bell Labs
Bell Laboratories is the research and development subsidiary of the French-owned Alcatel-Lucent and previously of the American Telephone & Telegraph Company , half-owned through its Western Electric manufacturing subsidiary.Bell Laboratories operates its...

 (1997–2002) claimed to have developed an electrically pumped laser based on tetracene. However, his results could not be reproduced, and it is considered to be scientific fraud.
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