Walter+Hietler+and+Fritz+London

Sahana Kapilan, Maddie Millward, Ben Mckendry, Chloe Van

@http://www.youtube.com/watch?v=23u_Ap_8hxI

__SCRIPT:__ Sahana

Welcome to SCIENCE CORNER! Today we will discuss two amazing chemists who advanced the understanding of covalent bonds in compounds. The information that these two scientists found is now studied in textbooks and in classes globally. These two have a lot of history and we’ll take a quick look at their successes. Walter Heitler and Fritz London worked together in their early chemist years, they studied the covalent bonds with the crucial information about quantum mechanics discovered by Heisenberg and Schrödinger. I have some footage of these chemists at work… They met in Zurich in 1927 when they discovered the necessary components to mixing chemicals and creating new useful substances that we use in our everyday lives and published the book “Zeitschrift Fur Physik”. The Heitler-London theory was formulated which for the first time enabled the calculation of bonding properties of the hydrogen molecule // H // // 2 // based on quantum mechanical considerations. Specifically, Walter Heitler determined how to use Schrödinger’s wave equation (1925) to show how two hydrogen atom wave functions join together, with plus, minus, and exchange terms, to form a covalent bond. He then called up his associate Fritz London and they worked out the details of the theory over the course of the night. (footage of ben and maddie ‘working’). The valence bond theory of bonding was mainly developed by Walter Heitler and Fritz London in 1927, and later modified by Linus Pauling. Each scientist won a number of awards, as well as one that they one together. Fritz won the Lorenz Medal in 1953. Walter Heitler won the Deutsche Physikalische Gesellschaft Max-Plank Medal in 1968 and the Marcel Benoist Pruze urn 1969. Together these two young inspiring scientists won the Gold Medal of the Humboldt Gesellschaft. Now lets talk a bit more about each of the scientists personal lives. Fritz Wolfgang London was born in Germany on March 7, 1900. London’s early work included the discoveries with Heitler as well as his own discoveries in the area of intermolecular forces and he worked with his brother Heinz on superconductivity and discovered the London equations. Early work in London in intermolecular forces. He created the expression “disperostion effect” for the interaction between two rare gas atoms at large (about one nanometer distance apart). One interesting event that obstructed Fritz’s work and studies was that in 1933 Fritz and his brother had to flee to England due to the Nazi racial laws. Walter Heitler was born in Germany on January 2, 1904. He studied physics at [|Karlsruhe] [|Technische Hochschule], [|Humboldt University of Berlin] , and at [|Ludwig Maximilians University of Munich]. In 1922 he began is study of physics at the universities mentioned. He obtained his doctorate in 1926 for physics and mechanical studies. From 1926-1927 he was a Rockefeller Foundation Fellow for postgraduate research. At the University of Copenhagen he studied under Neils Bohr the famous chemist who discovered ad created tho Bohr diagram for a better understanding of an elements atom. An interesting fact about this hard working chemist is that he also wrote a number of books, one of which is titled “The Quantum Theory of Radiation”, which marked future developments in quantum mechanics. Here’s a picture of a copy of the book that can be found in multiple languages, including Russian, german, English, and French. That’s all for Science Corner today, see you next time!

__@http://phys.bspu.unibel.by/hist/physport/gif/phys/heitler.jpg__ Walter Heitler, Fritz London, and Ava Helen Pauling in Europe. 1926.

__http://images.google.ca/imgres?imgurl=http://osulibrary.oregonstate.edu/specialcollections/coll/pauling/catalogue/09/1926i.117-600w.jpg&imgrefurl=http://osulibrary.oregonstate.edu/specialcollections/coll/pauling/bond/pictures/1926i.117.html&usg=__jO5KIgMRx19uTsGrIA854Ha_zyI=&h=504&w=600&sz=58&hl=en&start=5&sig2=8Cqx4wVsFfirXK_5278JXw&um=1&tbnid=02lRNGK6Hnb_kM:&tbnh=113&tbnw=135&prev=/images%3Fq%3Dwalter%2Bheitler%26hl%3Den%26sa%3DN%26um%3D1&ei=ekFnS5O5NI7itQOW29TmAg__ Linus and Ava Helen Pauling in Munich, with Walter Heitler (left) and Fritz London (right), 1927. __@http://osulibrary.oregonstate.edu/specialcollections/coll/nonspcoll/catalogue/heitler-london-600w.jpg__ Heinz and Fritz __@http://www.phy.duke.edu/history/DistinguishedFaculty/FritzLondon/MyerLondon.jpg__ __@http://photos.aip.org/history/Thumbnails/wills_laboratory_e1.jpg__