Peter Joseph William Debye (March 24, 1884–November 2, 1966) was a Dutch physicist and physical chemist, and Nobel laureate in Chemistry.

He studied mathematics and classical physics, and in 1905 received a degree in electrical engineering.
In 1906, Sommerfeld received an appointment at Munich, and took Debye with him as his assistant.
In 1907 he published his first paper, a mathematically elegant solution of a problem involving eddy currents. At Aachen he studied under the theoretical physicist Arnold Sommerfeld, who later claimed that his most important discovery was Peter Debye.
He got his Ph. D. with a dissertation on radiation pressure in 1908.
In 1910 he derived the Planck radiation formula using a method which Max Planck agreed was simpler than his own method.
In 1911, when Albert Einstein took an appointment as a professor at Prague, Debye took his old professorship at Zürich. This was followed by moves to Utrecht in 1912, Göttingen in 1913, back to Zürich in 1920, to Leipzig in 1927, and to Berlin in 1934, where he became director of the Kaiser Wilhelm Institute, saw to the construction of new laboratories, and developed it into the now-world-regarded Max Planck Institute in 1938.
In 1913 he married Mathilde Alberer. They had a son and a daughter; their son (Peter P. Debye) became a physicist and collaborated with Debye in some of his researches
In 1914-1915, he calculated the effect of temperature on X-ray diffraction patterns of crystalline solids with Paul Scherrer.
In 1923, with his assistant Erich Hückel, he developed an improvement of Svante Arrhenius' theory of electrical conductivity in electrolytic solutions. Although an improvement was made to the Debye-Hückel equation in 1926 by Lars Onsager, the theory is still regarded as a major forward step in our understanding of electrolytic solutions.
In 1938 the Nazi government began to insist that Debye give up his Dutch citizenship and become a German citizen. Debye did not want to do so, and since he had been offered a chance to give a series of lectures at Cornell University in Ithaca, New York, traveled to the United States of America.
In April 1966 he suffered a heart attack, and in November of that year a second, which proved fatal.
Awards and honors:
1930 - Rumford Medal for work relating to specific heats and X-ray spectroscopy
1937 - Franklin Medal from The Franklin Institute.
1936 - Nobel Prize in Chemistry (entry at nobelprize.org) "for his contributions to the study of molecular structure," primarily referring to his work on dipole moments and X-ray diffraction
1963 - Priestley Medal
1965 - National Medal of Science