MicroscopyPioneers
Pioneers in Optics: Alexander Jablonski (1898–1980)
Cameron Varano Casasanta AAAS Science and Technology Policy Fellow, US Department of Defense
cameron.varano@
gmail.com Note: Tis article is from the website Molecular Expressions™, created by the late Michael Davidson and now maintained by Eric Clark, National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32306.
Alexander Jablonski, who
would one day come to be known as the father of fluorescence spec- troscopy, was born on Febru- ary 26, 1898, in Voskresenovka, Ukraine. He began his formal journey into the field of atomic physics in 1916 at the University of Kharkov but was soon delayed due to his service in the military. In 1918, when Poland once again became an independent state aſter over 120 years of occupa- tion, Jablonski moved to Warsaw and entered the university there to continue his education. He was, however, forced to postpone his study of physics for a time in 1920 when he again undertook military service, this time in the Polish-Bolshevik war. Jablonski returned to the University of Warsaw in 1921
where he studied under Stefan Pienkowski. He also began playing first violin at the Warsaw Opera, an activity he continued for five years before relinquishing it to fully concentrate on scientific endeavors. Despite the various interruptions he had endured, Jablonski received his doctorate in 1930. His doctoral dissertation, entitled “On the Influence of the Change of Wavelengths of Excitation Light on the Fluorescence Spectra,” concerned what would become the primary focus of his professional career. Following the bestowal of his well-deserved degree, Jablon-
ski remained at the university, continuing both theoretical and experimental work in the Department of Experimental Phys- ics. Tere he closely examined the effects of pressure on atomic spectral lines in gases and was particularly interested in the polarization of photoluminescence in solutions. To explain experimental evidence gained in the field, Jablonski differenti- ated the transition moments in absorption and in emission and analyzed an assortment of factors responsible for the depolar- ization of luminescence. His work resulted in the introduction of what is now known as a Jablonski Energy Diagram (Figure), a tool that can be used to explain the kinetics and spectra of fluorescence, phosphorescence, and delayed fluorescence. Jablonski diagrams are often used as a starting point for discussions regarding the absorption and emission of light.
46 doi:10.1017/S1551929522000852
A typical Jablonski diagram illustrates a singlet ground elec- tronic state, as well as a singlet first, and sometimes a second, electronic excited state. At each energy level, fluorophores can exist in a number of vibrational energy levels, which are represented by multiple horizontal lines drawn for each electronic state. Transitions between states are depicted by vertical lines that traverse the region between the ground and excited states. Jablonski’s scientific efforts were halted once again when
Germany invaded Poland and World War II began. He served as a member of the Polish Army from 1939 to 1945 and was taken prisoner for a time, first by the German Army and then by the Soviet Army. Jablonski returned to Poland in 1946, to a country completely crippled by the war. In the difficult postwar years, he was elected to chair the Department of Physics at the new Nicholas Copernicus University in Torun. Despite the adverse circumstances in which it was organized, the department under Jablonski’s direction became an important center for scientific inquiry into atomic and molecular physics. Jablonski officially retired from the university in 1968 but continued in his private research for many years before his death on September 9, 1980.
www.microscopy-today.com • 2022 July
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72
