Chemistry

Supramolecular chemistry studies how intermolecular interactions organize molecules into larger assemblies with distinctive structures, properties, and functions.

Thermodynamic activity is a dimensionless measure of a substance’s chemical potential relative to a specified standard state, accounting for nonideal behavior.

Titration is a quantitative analytical method that determines the amount of a substance from its reaction with a measured quantity of another reagent.

A transition state is the barrier-crossing configuration or ensemble of configurations separating reactants from products in an elementary chemical reaction.

A unit cell is a repeating region of a periodic crystal structure, defined by lattice vectors and described by its geometry and atomic contents.

Valence bond theory describes chemical bonding through localized orbitals, electron spin coupling, and resonance between contributing electronic structures.

A valence electron is an electron in an atom’s chemically active outer electronic structure, principally responsible for bonding and chemical reactivity.

Van der Waals forces are nonbonding interactions arising from permanent or induced electric dipoles, influencing molecular cohesion, adsorption, and material structure.

Water (H₂O) is a polar molecule whose hydrogen-bonded network gives it unusual physical properties, makes it a universal solvent, and underpins life and Earth's climate.

X-ray crystallography determines atomic and molecular structures by analyzing the diffraction of X-rays by crystals.