|
The start of our story is bound up initially with the
discovery of the electron, subsequently with the mysteries of quantum theory
together with observations about atomic spectra. |
| 1823 |
André-Marie Ampére - associated
magnetism with the motion of electric charge. |
| 1834 |
Michael Faraday's experiments on
electrolytes. |
| 1891 |
George Johnstone Stoney "names" the
electron. |
| 1897 |
J.J.Thompson measures e/m for the
electron. |
| 1900 |
Joseph
Larmor published his collected papers on electromagnetism in 1900 in his
book "Aether and Matter". |
| 1921 |
Stern and Gerlach's
experiment. |
| 1924 |
Louis de Broglie proposed that
had both wave and particle properties. |
| 1925 |
Pauli's Exclusion
Principle |
| 1925 |
Samuel Goudsmit and George Uhlenbeck
discovered electron spin |
| 1928 |
Paul Dirac showed that the spin
quantum number appears automatically if a relativistic Hamiltonian is used for
the wave equation. |
| |
After 1925 there were numerous related measurements and theoretical
developments, - molecular beam experiments, also resonant molecular beam
experiments, the prediction of resonant absorption, microwave measurements on
small molecules, and spin lattice relaxation measurements. Then in World War II
high power microwave generators (magnetrons) and low power microwave oscillators
(klystrons) and other electronics were developed for use with Radar. After the
war these devices were incorporated in early EMR spectrometers. However there
were a number of important observations before the first resonance experiments,
in particular three still impinge strongly on modern EMR experiemnts. The
Kramers theorem, the Breit Rabi formulae and early experiments on spin lattice
relaxation. Hovering behind all of this is the figure of Paul Dirac. |
| 1930 |
The Kramers Theorem. |
| 1931 |
The Breit Rabi
formulae |
| 1932 |
Spin Lattice
Relaxation. |
| 1939 |
Rabi and associates -
first experimental observation of magnetic resonance |
| 1944 |
Evgeny Zavoisky - first
measurement of Electron Paramagnetic Resonance in Kazan State
University. |
| 1946 |
Felix Bloch's famous equations -
Physical Review, 1946, 70, 460. |
| 1946 |
First electron resonance measurements of gases by R.Beringer and co-workers |
| 1952 |
ODMR - optically
detected magnetic resonance |
| 1956 |
ENDOR measured by George
Feher |
| 1966 |
Ernst and Anderson's specification for FT-PMR |
| 1974 |
Yacob Lebedev - first VHF EPR
experiments |
| 1974 |
First NMR imaging experiments. See also EMRF online |
| 1980 |
Röder's FT-PMR
machine |
| 1986 |
Jack Freed's's first FT and 2D EPR Experiments |
| 1994 |
Jorg Wrachtrup, Jurgen Kohler, E.J.J. Groenen and Christian von
Borzyskowski carry out the first single molecule EPR experiment. |
Timeline
