<?xml version="1.0" encoding="utf-8"?><mads xmlns="http://www.loc.gov/mads/" xmlns:mods="http://www.loc.gov/mods/v3" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.loc.gov/mads/
mads.xsd"><authority><topic authority="http://AATesaurus.cultura.gencat.cat/aat/getty_en">molecules</topic></authority><related type="narrower"><topic>macromolecules</topic></related><related type="narrower"><topic>carbon nanotubes</topic></related><related type="broader"><topic>material components</topic></related><variant type="other"><topic>molecule</topic></variant> <note xml:lang="en"><![CDATA[ The smallest components of a compound that can exist  independently and retain their properties. The atoms that make up a molecule are either bonded together covalently, as in carbon dioxide, or electrovalently, as in sodium chloride.   ]]></note></mads>