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Molecule, a group of two or more atoms that form the smallest identifiable unit into which a pure substance can be divided and still retain the composition and chemical properties of that substance. Learn more about the properties and structures of molecules in this article.

A pure substance is composed of molecules with the same average geometrical structure. The chemical formula and the structure of a molecule are the two important factors that determine its properties, particularly its reactivity. Isomers share a chemical formula but normally have very different properties because of their different structures.

A chemical structure of a molecule is a spatial arrangement of its atoms and their chemical bonds. Its determination includes a chemist 's specifying the molecular geometry and, when feasible and necessary, the electronic structure of the target molecule or other solid.

2025年1月16日 · 2.1: Chemical Bonding. 2.1.1: Types of Chemical Bonds; 2.1.2: Electronegativity and the Bonding Continuum; 2.1.3: Polarizability and Percent Ionic Character

2023年1月30日 · Molecular geometry, also known as the molecular structure, is the three-dimensional structure or arrangement of atoms in a molecule. Understanding the molecular structure of a compound can help determine the polarity, reactivity, phase of matter, color, magnetism, as well as the biological activity.

The Journal of Molecular Structure is dedicated to the publication of full-length articles and review papers, providing important new structural information on all types of chemical species including: • Stable and unstable molecules in all types of environments (vapour, molecular beam, liquid, … View full aims & scope

2025年1月30日 · Hydrogen atoms in polar bonds within any molecule can form bonds with other adjacent molecules. For example, hydrogen bonds hold together two long strands of DNA to give the DNA molecule its characteristic double-stranded structure. Hydrogen bonds are also responsible for some of the three-dimensional structure of proteins.

The primary structure is the covalent chemical structure, that is, a specification of the identity of all the atoms and the bonds that connect them. The major molecules with which we work—proteins, nucleic acids, and carbohydrates— usually consist of linear arrays of units, each of which has a similar overall structure; they differ only in ...