The smallest particles of matter that is known to exist are quarks. Quarks combine together to make hadrons. The most common hadrons are protons and neutrons. Protons neutrons and/or electrons combine together to make an atom. So the answer is no, atoms are NOT the smallest particle of matter
Smallest particle is called a quark. A quark makes up the nucleus of an atom. There are a total of 6 types of quarks. Snippets.com/what-is-the-smallest-subatomic-particle.htm