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How do enantiomers differ from other stereoisomers called diastereomers?

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Two diagrams show the three-dimensional structure of a methane molecule: panel A uses a ball-and-stick model with a central carbon atom connected to four hydrogen atoms in a tetrahedral arrangement, while panel B illustrates the bond angle of 109.5 degrees and bond length of 1.09 angstroms between carbon and hydrogen atoms. — isomerism Tetrahedral geometry of methane: (A) stick-and-ball model and (B) diagram showing bond angles and distances. (Plain bonds represent bonds in the plane of the image; wedge and dashed bonds represent those directed toward and away from the viewer, respectively.)

In chemistry, stereoisomers are molecules with the same atomic composition but different spatial orientations. They are categorized into two primary types: enantiomers and diastereomers.

Key Differences

Mirror-Image Relationship: Enantiomers are non-superimposable mirror images of each other, similar to the relationship between a right and left hand. Diastereomers are stereoisomers that are not mirror images of one another.1234
Physical and Chemical Properties: Enantiomers possess identical physical and chemical properties, such as melting points and densities, except in their interactions with other dissymmetric molecules or polarized light. Conversely, diastereomers do not need to have similar properties; they can differ significantly in their physical and chemical behavior, much like structural isomers.234
Definition: If two stereoisomers are not enantiomers, they are classified as diastereomers.14

Essentially, while enantiomers represent a specific "mirror-image" symmetry, diastereomers encompass all other non-superimposable stereoisomeric relationships.13