Oxynitrates

Oxynitrates are a group of chemical compounds that contain oxygen, nitrogen, and at least one other element. They are distinct from nitrates, which are specifically salts or esters of nitric acid (containing the NO3- anion). The term oxynitrate can refer to a broader range of compounds where oxygen and nitrogen are bonded to other atoms.

In atmospheric chemistry, oxynitrates often refer to peroxyacyl nitrates (PANs) and their derivatives. These are secondary pollutants formed in the troposphere through photochemical reactions involving nitrogen oxides and volatile organic compounds. PANs are important because they can act as carriers of nitrogen oxides over long distances, contributing to regional air pollution and ozone formation in areas away from the original source of emissions. They are also irritants to the eyes and respiratory system.

Beyond atmospheric science, the term oxynitrate can be used in inorganic chemistry to describe compounds containing a nitrate anion (NO3-) coordinated to a metal cation or bonded to another element in a way that differentiates it from simple nitrate salts. For example, certain coordination complexes might be referred to as oxynitrates if the nitrate ligand is present alongside other oxygen-containing ligands or in a specific structural arrangement. The precise definition and usage can vary depending on the context of the chemical system being studied.