01940nas a2200229   4500008004100000022001400041245005900055210005900114260000800173300001400181490000700195520116800202100003001370700001901400700004801419700002501467700002501492700003201517700003601549700003101585856009401616       2020                        eng d  a0003-270000aGeometrical isomerism directed electrochemical sensing0 aGeometrical isomerism directed electrochemical sensing  cMAR  a4541-45470 v923 a<p>We report the independent role of isomerism of secondary sphere substituents over their nature, a factor often overlooked in molecular electrocatalysis pertaining to electrochemical sensing, by establishing that isomerism redefines the electronic structure at the catalytic reaction center via geometrical factors. UV-vis spectroscopy and X-ray photoelectron spectroscopy suggest that a substituent's isomerism in molecular catalysts conjoins molecular planarity and catalytic activation through competing field effects and resonance effects. As a classical example, we demonstrate the influence of isomerism of the -NO2 substituents for the electrocatalytic multi electron oxidation of As(III), a potentially important electrochemical pathway for water remediation and arsenic detection. The isomerism dependent oxidative activation of catalytic center leads to a nonprecious molecular catalyst capable for direct As(III) oxidation with an experimental detection limit close to WHO guidelines. This work opens up an unusual approach in analytical chemistry for developing various sensing platforms for challenging chemical and electrochemical reactions.</p>
1 aKottaichamy, Alagar, Raja1 aBegum, Shabbah1 aDevendrachari, Mruthyunjayachar, Chattanaha1 aBhat, Zahid, Manzoor1 aThimmappa, Ravikumar1 aKotresh, Harish, Makri Nimb1 aVinod, Chathakudath, Prabhakara1 aThotiyl, Musthafa, Ottakam  uhttps://library.ncl.res.in/content/geometrical-isomerism-directed-electrochemical-sensing