In Chemistry World, Laurence Lavelle is interviewed about placement of the Group 3 elements in the periodic table, and the d-block and f-block elements.
In the article titled “New rationale for 15-element wide f block”, which was published in the May 21, 2018 issue of the Royal Society’s Chemistry World on-line magazine, Lavelle discussed the question as to why the original and widely used visual depiction of the periodic table with Sc ([Ar] 3d1 4s2), Y ([Kr] 4d1 4s2), La ([Xe] 5d1 6s2), and Ac ([Rn] 6d1 7s2) are all in group 3 as the first d-block element.
In the interview he explains that 1. it is consistent with their three outer valence electrons and d1 state, 2. the organization of the periodic table with the s-block (2 groups), the p-block (6 groups), the d-block (10 groups), and the f-block (14 groups), and 3. the recent Phys. Chem. Chem. Phys. paper by Joshi et al. showing La and Ac form structures that are similar to stable 18-electron d-block transition-metal complexes.
“Given the similarities of lanthanum, actinium, lutetium and lawrencium discussed in the paper, all showing 18-electron transition-metal d block chemistry, the difficulty now arises as to how best to illustrate this in the periodic table” Lavelle states in the article. “Placing all four elements in the f block is visually appealing but is contrary to [the rest of] the periodic table and is also contrary to the findings of their paper as all four elements are shown to exhibit compound properties associated with d block elements. The best representation still appears to be the original and widely used visual depiction of the periodic table with scandium, yttrium, lanthanum and actinium all in group 3 as the first d block elements, which is consistent with their three outer valence electrons and d1 state.”
A native of Ireland, Lavelle completed his B.Sc. (Chemistry major, and Microbiology and Physical Oceanography minors), B.Sc. (Honors, Chemistry), and M.Sc. (Distinction, Physical Chemistry) at the University of Cape Town (UCT). After graduating from UCT he accepted a faculty position in the Chemistry Department at the University of The Witwatersrand (WITS), South Africa. He then moved to the United States and his M.A. and Ph.D. are both in Molecular Biophysics from Princeton University. After one year as a post-doctorate at UCLA’s Molecular Biology Institute he joined the faculty in the department of Chemistry and Biochemistry where he currently, per year, teaches over two thousand enrolled students and supervises over fifty teaching assistants and undergraduate assistants.
He is the recipient of many research and teaching awards including the Sir Robert Kotze Award, the Harry Crossley Award, a CSIR Fellowship, Berlex Fellowship, Molecular Biophysics NIH Fellowship, the Herbert Newby McCoy Award for Innovative Research at UCLA, the Hanson-Dow Award for Teaching Excellence at UCLA, the UCLA AAP Faculty Recognition Award, and UCLA’s highest teaching award the University Distinguished Teaching Award.
Recent awards (2016-17) include Sigma Pi’s Professor of Empowerment Award (2016), UCLA Faculty Development Award (2016 and 2017), and a UCLA Office of Instructional Development, Mini-Grant Award (2016 and 2017).
Lavelle has published in the areas of host-guest chemistry, the periodic table, DNA and RNA stability and structure, and virus stability and self-assembly. He is a member of the American Association for the Advancement of Science, the American Chemical Society, the American Physical Society, the Biophysical Society, Sigma Xi, The Royal Society of Chemistry, and the American Federation of Teachers.
To learn more about Lavelle, visit his homepage.
