Isotopide

Isotopide is a fictional or hypothetical chemical compound used in teaching and thought experiments to illustrate the effects of isotopic substitution in solids and molecules. It is not known to exist as a real substance, but is described in educational materials as a simple binary crystalline compound that can exist in multiple isotopic varieties.

Conceptually, isotopide is described as a rigid lattice of two elements, A and B, with the ability to replace one isotope of A or B with a heavier or lighter variant without changing the chemical identity. This substitution alters properties that depend on mass, such as vibrational frequencies and zero-point energy, while leaving chemical reactivity largely unchanged.

Predicted properties include shifts in Raman and infrared spectra, slight changes in lattice parameters, and small variations in heat capacity at low temperatures. Because it is a hypothetical construct, exact values vary by model, but the key idea is that isotopic mass affects physical properties without altering chemical formula.

Education and computational chemistry use isotopide to demonstrate isotopic effects, including the concept of isotopologues and isotopic mixtures. In practice, researchers simulate isotopide in lattice dynamics or ab initio calculations to study how isotopic composition influences thermodynamic and spectroscopic properties.

Safety and hazards are not defined for isotopide since it is not a real material; standard lab safety emphasizes that real substances must be handled according to their actual properties.