| Théophile de Donder | |
| Birth Date: | 19 August 1872 |
| Birth Place: | Brussels, Belgium |
| Death Place: | Brussels, Belgium |
| Nationality: | Belgian |
| Fields: | Physicist and mathematician |
| Workplaces: | Université Libre de Bruxelles |
| Alma Mater: | Université Libre de Bruxelles |
| Academic Advisors: | Henri Poincaré |
| Doctoral Students: | Ilya Prigogine Léon Van Hove Théophile Lepage |
| Known For: | Being the father of irreversible thermodynamics |
Théophile Ernest de Donder (in French də dɔ̃dɛʁ/; 19 August 1872 – 11 May 1957) was a Belgian mathematician, physicist and chemist famous for his work (published in 1923) in developing correlations between the Newtonian concept of chemical affinity and the Gibbsian concept of free energy.
He received his doctorate in physics and mathematics from the Université Libre de Bruxelles in 1899, for a thesis entitled Sur la Théorie des Invariants Intégraux (On the Theory of Integral Invariants).[1]
He was professor between 1911 and 1942, at the Université Libre de Bruxelles. Initially he continued the work of Henri Poincaré and Élie Cartan. From 1914 on, he was influenced by the work of Albert Einstein and was an enthusiastic proponent of the theory of relativity. He gained significant reputation in 1923, when he developed his definition of chemical affinity. He pointed out a connection between the chemical affinity and the Gibbs free energy.
He is considered the father of thermodynamics of irreversible processes.[2] De Donder's work was later developed further by Ilya Prigogine. De Donder was an associate and friend of Albert Einstein.He was in 1927, one of the participants of the fifth Solvay Conference on Physics, that took place at the International Solvay Institute for Physics in Belgium.