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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Abhik Ghosh | 2/2 | https://en.wikipedia.org/wiki/Abhik_Ghosh | reference | science, encyclopedia | 2026-05-05T16:42:54.462936+00:00 | kb-cron |
Ghosh has contributed to many areas of porphyrin-related research. Computational bioinorganic chemistry. In the 1990s, Abhik reported some of the first large-scale ab initio and density functional theory calculations on porphyrins and other bioinorganic systems, helping lay the foundation of the vibrant field of computational bioinorganic chemistry (or quantum bioinorganic chemistry). During this period, he shed light on the problem of diatomic ligand discrimination by heme proteins, debunking the then-prevalent steric model and emphasizing the key role of hydrogen bonding in the distal pocket. He also reported some of the first first-principles calculations on high-valent iron-oxo species. Transition metal spin state energetics. In the 1990s, Abhik (partly in collaboration with Peter Taylor at the San Diego Supercomputer Center) showed that common exchange-correlation functionals yield highly divergent results on the energetics of low-energy spin states of transition metal complexes. He showed that classic pure functionals tend to unduly favor lower-spin states, while hybrid functionals such as B3LYP err in the other ditrections, favoring higher-spin states. Subsequently, he showed that GGA functionals based on the OPTX exchange functional sometimes provide a good solution to the problem, as does B3LYP* (with a lower proportion of exchange relative to B3LYP). However, a functional yielding the best spin state energetics does not necessarily yield the best results for other properties such as bond distances and spin densities. Noninnocent ligands. He has had an abiding interest in the phenomenon of ligand noninnocence and has contributed substantially to studying the phenomenon in transition metal corroles derivatives. Subsequently, he has used multiconfigurational ab initio calculations to tackle the longstanding question of local oxidation states in transition metal nitrosyls. Heavy element chemistry. From 2010 onward, he has developed the field of heavy element corrole derivatives, which are unusual size-mismatched metal-ligand assemblies that incorporate a large 4d or 5d transition metal ion within the sterically compressed central cavity of a corrole. In this area he has reported some of the first examples of 99Tc, rhenium, osmium, platinum, and gold corroles. Despite their size-mismatched character, many of these complexes have proved rugged and found applications as near-IR phosphorescent photosensitizers in oxygen sensing and photodynamic therapy as well as in dye-sensitized solar cells. Low-barrier hydrogen bonds and tautomerism. Early in his career, Abhik used X-ray photoelectron spectroscopy (XPS) to study short-strong hydrogen bonds in porphyrin-type molecules. Years later, he reported the first example of a stable cis tautomer of a free-base porphyrin in the form of a termolecular hydrogen-bonded complex. Subsequently, they found additional examples of porphyrin cis tautomers, proving that they can be reliably obtained from virtually any strongly saddled porphyrin co-crystallized with two molecules of a hydrogen donor (typically water or an alcohol). Miscellaneous. Abhik has contributed significantly to a variety of problems in physical organic and physical inorganic chemistry, including transition metal complexes with unusually low and high coordination numbers, stereochemistry of sandwich compounds, metal-metal quadruple bonds and quintuple bonds, transition metal carbides, low-valent main-group species, and the perfluoro cage effect.
== Science communication ==
In collaboration with linguist Paul Kiparsky, Ghosh has written about the possible influence of Pāṇini's Sanskrit grammar, in particular the periodic Sanskrit alphabet (the Shiva sutras), on Mendeleev's conception of the periodic table, a potentially important, new insight into the history of the periodic table. Ghosh has also published popular articles on arrow pushing, on the occasion of the 100th anniversary of its first use by Sir Robert Robinson, and on the impact of relativity in chemistry, among many others. As a queer chemist, Ghosh has been involved in a variety of diversity initiatives. The 2011 book Letters to a Young Chemist with a young woman as the protagonist and several contributions by leading female scientists has gone through numerous reprints and remains a bestseller. In 2020–2021, Ghosh published two biographical essays on the late Martin Gouterman, a noted porphyrin chemist and one of the first openly gay/LGBT scientists, drawing a parallel with astronomer and gay rights activist Frank Kameny (see LGBT history for a more general discussion). Subsequently, he co-edited a Virtual Issue on “Out in Inorganic Chemistry: A Celebration of LGBTQIAPN+ Inorganic Chemists” highlighting queer authors in Inorganic Chemistry and other American Chemical Society journals.
== Personal life == Ghosh identifies as "bi but mostly gay."
== References ==
== Further reading == Buntrock, R. E. (January 2012). "Review: Letters to a Young Chemist". Choice. p. 913.