Chemical Bonding? Playing catch with electrons!
Chemical Bonding? Playing catch with electrons!
Abstract: Quantum mechanical electron tunneling is proposed as the mediator of chemical bonding. Covalent, polar covalent, ionic, and hydrogen bonds all rely on quantum mechanical tunneling, but the nature of tunneling differs for each bond type. Covalent bonding involves bidirectional tunneling across symmetric energy barriers. Polar covalent bonding involves bidirectional tunneling across asymmetric energy barriers. Ionic bonding occurs by unidirectional tunneling across an asymmetric energy barrier. A hydrogen bond is a three-atom bond in which an intermediate hydrogen atom acts as a bridge connecting two adjacent atoms via tunneling of the hydrogen electron.
The physics underlying chemical bond formation between atoms is analogous to baseball players playing catch. However, the rules for playing catch differ, depending on bond type. A covalent bond is similar to having two players playing catch with two balls and, furthermore, specifying that either player can throw a ball but that only one ball can be thrown at a time. In contrast, a polar covalent bond involves two players playing catch, but with only one ball. An ionic bond is a very boring type of baseball warm up since only one ball is involved and only one player can throw the ball. Finally, a hydrogen bond is similar to having three baseball players playing catch using one ball with the restriction than only throws between the central player and a non-central player are allowed.
In this presentation, the dynamic nature of chemical bonding is highlighted. Also, chemical bonding in the solid state is compared and contrasted to gas-state chemical bonding.
Speaker bio: Prior to his January 2018 retirement, John F. Wager held the Michael and Judith Gaulke Endowed Chair in the School of EECS at Oregon State University. He is the lead author of a book entitled ‘Transparent Electronics.’ Transparent electronics technology developed in his group at OSU was licensed to Hewlett-Packard Company who continued advanced joint-development with his group. This technology is finding emerging, high-value applications in flat-panel display thin-film transistor backplanes. In retirement, he occasionally dabbles in thin-film transistor device physics and in the physics of chemical bonding.
Related papers:
- John F. Wager and Douglas A. Keszler (2024), ACS Omega, https://pubs-acs-org.oregonstate.idm.oclc.org/doi/10.1021/acsomega.3c02736
- J. F. Wager (2024), ACS Omega, https://pubs-acs-org.oregonstate.idm.oclc.org/doi/full/10.1021/acsomega.3c05838?ref=recommended