Chemists are the scientists most directly responsible for studying elements, atoms, and molecules. They investigate the structures, properties, and reactions of matter at the atomic and molecular level. But chemistry is far from the only field involved. Physicists, materials scientists, biochemists, and several other specialists all study atoms and molecules, each from a different angle and for different purposes.
Chemists: The Primary Scientists of Matter
Chemistry is, at its core, the science of how atoms group together and follow physical laws. Chemists study the structures, physical properties, and chemical properties of material substances. That broad mission breaks into several specialties, each with its own focus.
Organic chemists study carbon-based compounds, their structures, properties, and reactions. Since carbon forms the backbone of everything from fuels to pharmaceuticals, organic chemistry is one of the largest and fastest-growing branches of the field. Inorganic chemists focus on metals, minerals, and other non-carbon-based substances. Analytical chemists develop methods to determine what a substance is made of and how much of each component it contains. Physical chemists sit at the boundary between chemistry and physics, studying how energy and forces govern molecular behavior.
Common job titles in the field include research chemist, atmospheric chemist, analytical chemist, and green chemist. Entry-level positions typically require a bachelor’s degree in chemistry or a related science field, while research roles usually call for a master’s degree or PhD. Chemists work in pharmaceutical development, environmental science, atmospheric research, and engineering, among other settings.
Physicists: Studying Atoms From the Inside Out
Where chemists focus on how atoms bond and react, physicists dig into the fundamental laws that govern atomic behavior. Atomic physicists study electron shells, energy levels, and the forces that hold atoms together. Nuclear physicists go deeper still, investigating the structure of the atomic nucleus itself and the mechanisms behind nuclear reactions.
The line between physics and chemistry blurs at this scale. Nuclear chemists, for instance, study how changes in the nucleus affect an atom’s electronic structure, while nuclear physicists focus on the mechanics within the nucleus. In practice, researchers in both fields often collaborate, and the distinction is less rigid than textbook definitions suggest. Physics provides the foundational rules that chemistry builds on: mathematics works with logical units, chemistry works with groups of atoms that follow physical laws.
Materials Scientists and Nanotechnologists
Materials science and engineering explores the structure, properties, and behavior of materials down to the molecular, atomic, and even subatomic levels. The goal is practical: creating goods and technologies that benefit society. Researchers in this field study everything from familiar substances like silicon, glass, metals, and plastics to exotic “designer materials” configured one atomic layer at a time.
The U.S. National Science Foundation invests heavily in this area, funding work on nanomaterials, biomaterials, ceramics, and metamaterials. Metamaterials are engineered substances with properties not found in nature, and they’re already showing up in fiber optics, solar panels, and advanced antennas. Modern tools make this atomic-scale work possible. Scanning tunneling microscopes (STMs) allow researchers to image and even physically move individual atoms on a surface. Scanning transmission electron microscopes (STEM) offer higher-throughput imaging for studying molecular and atomic arrangements. Both techniques can manipulate atoms in controlled environments, enabling a kind of atomic-scale fabrication that would have been unimaginable a few decades ago.
Biochemists and Molecular Biologists
When the question shifts from “what are atoms and molecules doing?” to “what are they doing inside living things?”, two closely related fields take over. Biochemists examine the chemical reactions happening in living organisms and their cells. They’re interested in the chemistry of life: how enzymes catalyze reactions, how cells generate energy, how nutrients get broken down and rebuilt.
Molecular biologists take a slightly different angle. They examine the structure of cells and the behavior of individual cellular components at the molecular level, focusing on how different molecules interact with each other inside living systems. The two fields overlap significantly, but the simplest distinction is that biochemists emphasize chemical reactions while molecular biologists emphasize molecular structures and interactions.
Geochemists and Astrochemists
Some scientists study elements and molecules not in a lab but across planets and galaxies. Geochemists analyze the elemental composition of Earth’s crust, oceans, and atmosphere to understand how our planet formed and continues to change. Astrochemists extend that work to astrophysical and planetary environments throughout the universe.
Astrochemistry is a genuinely multidisciplinary field. Researchers at NASA’s Goddard Space Flight Center, for example, investigate the origin and distribution of complex organic molecules in the early solar system, trying to understand what those compounds reveal about the history of solar system materials. Studying the abundance of various elements, ions, and molecules in space also helps scientists better understand Earth’s own geochemistry. One striking finding from this work: most of Earth’s carbon is locked in the planet’s core, with a substantial subsurface reservoir. Only a tiny percentage exists in the biosphere we interact with daily.
How These Fields Connect
The boundaries between these disciplines are real but porous. A materials scientist designing a new solar cell material draws on chemistry, physics, and engineering. An astrochemist analyzing molecules in a distant nebula uses techniques developed by analytical chemists and data models built by physicists. A biochemist studying a protein’s shape relies on the same X-ray crystallography methods that physicists and chemists use to map atomic structures in non-living materials.
If you’re a student figuring out which path leads to studying atoms and molecules, the answer depends on what draws you in. If you want to understand how substances react and transform, chemistry is the most direct route. If the fundamental forces inside atoms fascinate you, physics is the field. If you want to build new materials atom by atom, materials science is the path. And if you want to understand the molecular machinery of life, biochemistry or molecular biology will get you there. All of these scientists study elements, atoms, and molecules. They just ask different questions about them.