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Updated: Jun 17, 2026

Qualitative Identification of Carboxylic Acids, Boronic Acids, and Amines Using Cruciform Fluorophores
Published on: August 19, 2013
Bonding elucidation of the three common acids H2SO4, HNO3, and HClO4
Apostolos Kalemos1, Aristides Mavridis
1National and Kapodistrian University of Athens, Department of Chemistry, Laboratory of Physical Chemistry, PO Box 64 004, 157 10 Zografou, Athens, Greece. kalemos@chem.uoa.gr
Abstract:
The bonding nature of the non-hydroxyl oxygen atoms of the familiar acids sulfuric [(OH)(2)SO(2)], nitric (HONO(2)), and perchloric (HOClO(3)) is explained without using such ad hoc concepts of circular logic like "hypervalency". It is proposed here for the first time and confirmed through the help of coupled-cluster RCCSD(T) calculations, that the S(-O)(2), N(-O)(2), and Cl(-O)(3) bonding occurs by transfer of the electron pair densities of the central atoms, S, N, and Cl to the first excited state, (1)D, of the non-hydroxyl O atoms.
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