Loschmidt, Josef

In 1869 the Chemisch-Physikalische Gesellschaft (CPG, Chemical-Physical Society) was founded by the chemist Heinrich Hlasiwetz and the physicists Josef Loschmidt, Josef Petzval and Josef Stefan. Aims of the association were to further the development of chemistry and physics and to disseminate chemical and physical knowledge. This was to be achieved by ... 

In 1861 Johann Josef Loschmidt who was later to become a professor at the University of Vienna pri vately published a book con taming a structural formula for benzene similar to the one Kekule would propose five years later Loschmidt s book reached few readers and his ideas were not well known... 

The work on gas theory had many extensions. In 1865 Johann Josef Loschmidt used estimates of the mean free path to make the first generally accepted estimate of atomic diameters. In later papers Maxwell, Ludwig Boltzmann, and Josiah Willard Gibbs extended the rrratherrratics beyorrd gas theory to a new gerreralized science of statistical mechanics. Whenjoined to quantum mechanics, this became the foundation of much of modern theoretical con-derrsed matter physics. 

Rival schemes to the prism and hexagon included figures in which Josef Loschmidt used a large circle to signify neither atoms nor a ring structure for benzene but a structurally indeterminate benzene nucleus 82... 

Following the publication of stractural theory for all to examine, the next major players in its development were the Russian, Aleksandr Mikhailovich Butlerov (1828-1886), the Scot, Alexander Cmm Brown (1838-1922), and the Austrian, Joharm Josef Loschmidt (1821-1895). 

The third innovator of the early 1860s was the Austrian physicist Johann Josef Loschmidt, who, despite his work in chemistry, is not widely appreciated as a chemist. A portrait of him is shown in Figure 8. Loschmidt was bom in Pocena and began his university education at the German University of Prague. He completed his education at Vienna, but was unable to procure a teaching position there. He... 

Figure 8. Johann Josef Loschmidt (1821-1895) LOSCHMIDT1861 MODERN FORMULAS... 

H. G. Winkler Chemistry and philately, Josef Loschmidt , Chem. Labor. Biotech., 1996, 47, 66-68. 

The history of benzene is one of the most intriguing in science. It started in 1825 with the isolation of benzene by Michael Faraday from the condensed phase of pyrolyzed whale oil. Its planar cyclic structure was first proposed in 1861 by the Austrian physicist and physical chemist Johann Josef Loschmidt [1—5]. However, it was only fully understood some 70 years later, around 1930, with the advent of the modem theories of aromaticity, i.e. the theory of molecular orbitals (Hiickel s theory) [6-8] and the theory of resonance [9-12]. 

Johann Josef Loschmidt (1821-1895) attended Prague University, and then at 21 went to Vienna to study first philosophy and mathematics, and then the natural sciences, physics and chemistry. After industrial ventures making potassium nitrate and oxalic acid among other products, he returned to Vienna as a concierge in the early 1850s, and then became a school teacher. Always attracted by theoretical problems, he is also known for his calculation in 1865 of the number of molecules in one mL of gas (the Loschmidt number ). In 1866, he became Privatdozent at the University... 

In 1065. August Kekule presented a paper at the Academie des Sciences in Paris suggesting a cyclic structure for benzene, the inspiration for which he ascribed to a dream. However, was Kekule the first to suggest that benzene was cyclic Some believe not, and credit an Austrian schoolteacher. Josef Loschmfdt with the first depiction of cyclic benzene structures. In 1061,4 years before Kekule s dream, Loschmidt published a book in / v... 

There are still many invitations to give lectures, both on the history of chemistry and art. 1 am particularly proud of my work on Josef Loschmidt, who is finally being recognized as a great chemist. 

Boltzmann was born in Vienna, Anstria, and graduated from high school in Linz. He entered the University of Vienna in 1863, and he received his doctorate in physics three years later. Then, for two years, he served as assistant professor at the university, where he was strongly influenced by the atomistic thinking of physicists Josef Loschmidt and Josef Stefan. 

Before Kekule dreamed of his structure for benzene, Josef Loschmidt proposed the ring structure of the molecule. Unfortunately, Loschmidt did not publish his theory in a widely read scientific journal. As a result, the credit for this revolutionary theory is hotly debated today. 

Trupp, A. Energy, entropy On the occasion of the l(X)th anniversary of Josef Loschmidt s death in 1895 Is Loschmidt s greatest discovery still waiting for its discovery Phys. Essays 12(4), 614-628 (1999)... 

Fleischhacker, W., and T. Schonfeld, eds. Pioneering Ideas for the Physical and Chemical Sciences Josef Loschmidt s Contributions. New York Plenum,... 

Wotiz, John, and Christian Noe. "August Kekuie and Josef Loschmidt." In The Kekule Riddle, edited by John Wotiz, 221-45. Clearwater, FL Cache River Press, 1993. 

Johann Josef Loschmidt first calculated the value of Avogadro s number often referred to as the Loschmidt number in German-speaking countries Loschmidt constant now has another meaning). 

Loschmidt, Johann Josef (1821-1895) Austrian professor of physical chemistry at the University of Vienna in 1868. 

Wiswesser concluded that credit for the structure of benzene should be given to Johaim Josef Loschmidt Wiswesser, W. J. Aldrichimica Acta 1989, 22,17. 

In 1861 the Austrian chemist Johann Josef Loschmidt represented the benzene ring with a circle, but he made no attempt to indicate how the carbon atoms were actually arranged in the ting. 

Figure 1.2 Johann Josef Loschmidt (15 March 1821-8 Juiy 1895).

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