Francis William Aston

Francis William Aston ( born September 1, 1877 in Harborne / 1891 to Birmingham, † November 20, 1945 in Cambridge ) was an English chemist and physicist and Nobel laureate (chemistry 1922).

Life and work

Francis William Aston studied after completing his school career first chemistry. The former developments in physics led him to take up a scholarship in 1903 a further study of physics at the University of Birmingham near his birthplace Harborne, after its completion, he focused on the physics of the gas discharge tube. In this work he discovered during a glow discharge directly at the cathode before the first Kathodenlichtsaum a wafer-thin, dark layer after him the " Astonsche dark space " ( " Aston Dark Space" ) was named.

In 1909 he accepted an invitation from Sir Joseph John Thomson at the Cavendish Laboratory in Cambridge and dealt there with the identification of the neon isotopes. To this end, he lectured at Trinity College. His work was interrupted by the First World War, by the end of 1919 he returned again to his work. He developed during his research in 1901 a method of electromagnetic focusing of particle beams ( electromagnetic mass spectrograph ), which led to the development of the first mass spectrometer (1918). With its help, he identified more than 200 of the 287 naturally occurring isotopes. In 1919 he postulated the extremely high-energy fusion of hydrogen into helium. In 1922 he was awarded the Nobel Prize in Chemistry " for his discovery of isotopes, including the largely non-radioactive elements using his mass spectrograph and for his formulation of the " rule of integers ". This rule (Whole Number Rule - integer rule), also called the " Astonsche rule" or "( Astonsche ) isotope rule" according to him, saying: Chemical elements with odd atomic number have no more than two stable isotopes, those with even numbers on the other hand often have significant more. Francis William Aston made ​​it to the oxygen isotope 16O determined by formulating: " At a defined mass of the oxygen isotope [ 16O ] all other isotopes [ oxygen ] masses lie fairly close to integers. "

Even before his Nobel Prize, he was inducted into the Royal Society in 1921. Prominent among his publication are the works isotopes ( Isotopes, 1922) and Massenpektren and isotopes (Mass - Spectra and Isotopes, 1933). 1938, the Royal Medal of the Royal Society awarded him. In his honor, the moon crater " Aston " was named.