Physical chemistry
Physical chemistry applies physical principles and quantitative methods to explain the structure, energy, rates, and properties of chemical systems.
Thermodynamics: The study of energy, heat, work, and the macroscopic laws governing their transfer and transformation. It connects measurable energy changes to chemical equilibrium and spontaneity.
Chemical thermodynamics: The application of thermodynamic laws to chemical reactions, mixtures, and phase changes. It predicts equilibrium and the energetic favorability of chemical transformations.
Computational chemistry: The use of computational methods to model chemical structures, properties, and reactions. It uses physical models to predict chemical behavior when experiments alone are insufficient.
Organic chemistry: The study of carbon-containing compounds, especially their structures, reactions, and synthesis. It organizes knowledge chiefly around compound families and transformations rather than physical explanation.
Quantum mechanics: The theory describing matter and energy at atomic and subatomic scales through quantized states and probabilities. It explains atomic structure, chemical bonds, and molecular spectra.
Transition state theory: A theory that estimates reaction rates from the properties of a high-energy configuration between reactants and products. It connects molecular-scale energy barriers to measured reaction rates.
Surface science: The study of the physical and chemical properties of surfaces and interfaces. Surface energetics and molecular interactions explain catalysis and adsorption.
Inorganic chemistry: The study of compounds outside the main scope of organic chemistry, including metals, minerals, and coordination complexes. It is organized around broad classes of substances, while physical chemistry emphasizes governing principles.
Statistical mechanics: The framework that derives macroscopic properties from the statistical behavior of microscopic particles. It links molecular motion and interactions to bulk chemical properties.
Potential energy surface: A map of a molecular system’s potential energy as a function of its nuclear positions. Its shape describes stable structures and pathways between chemical states.