Definition

1. Adjective:
   • Pertaining to or characterized by allomerism: Describes a substance, especially a crystalline solid, whose chemical composition can vary while its crystalline structure remains unchanged.

Usage

• The term "allomerous" is a specialized scientific adjective used primarily in chemistry, mineralogy, and materials science. It describes a specific type of variation in chemical composition without a change in form.
• It is typically used attributively (before a noun) to modify the name of a substance or series.

Examples

• Adjective:
  • The mineral series exhibits allomerous characteristics, with iron and magnesium freely substituting for each other.
  • Researchers studied the allomerous relationship between the two crystalline compounds.

Advanced Usage

• "Allomerous variation": Refers specifically to the phenomenon of variable composition within an isomorphous series.
  • The allomerous variation in the olivine group is well-documented.

Variants and Related Words

• Allomerism (n): The condition or phenomenon of having variable chemical composition without change in crystalline form.
  • The concept of allomerism is important in understanding solid solutions.

Synonyms

• Isomorphous (in a specific context): Having the same crystalline form but potentially different chemical composition. (Note: "Isomorphous" is a broader term; "allomerous" specifically implies compositional variation.)

Notes on Meaning

• The core concept of "allomerous" hinges on the distinction between form (structure) and composition (chemical makeup). An allomerous substance maintains a constant external crystalline form despite internal chemical variation.
• It is often contrasted with polymorphous substances, which have the same composition but different crystalline structures.

Adjective

1. pertaining to allomerism