isomerism (redirected from constitutional i.)

isomerism /isom·e·rism/ (-ah-rizm) the possession by two or more distinct compounds of the same molecular formula, each molecule having the same number of atoms of each element, but in different arrangement.

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constitutional i.  isomerism in which the compounds have the same molecular formula (that is, they are composed of the same atoms) but differ in structure, the atoms being linked in different ways.

Constitutional isomerism. Both compounds have the molecular formula C4H10.

geometric isomerism  stereoisomerism in which isomers differ in the arrangement of substituents of a rigid structure, such as double-bonded carbon atoms or a ring.

optical isomerism  stereoisomerism in which isomers differ in the arrangement of substituents at one or more asymmetric carbon atoms; thus some, but not necessarily all, are optically active.

structural isomerism  constitutional i.

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i·som·er·ism (-sm-rzm)

n.

1. The phenomenon of the existence of isomers.

2. The complex of chemical and physical phenomena characteristic of or attributable to isomers.

3. The state or condition of being an isomer.

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isomerism (ī·sōˑ·mer·i·zm),

n dissimilar arrangement of atoms within the molecules of two chemical compounds that have identical molecular formulae. See also geometric isomerism and optical isomers.

Isomerism.

isomerism, geometric,

n a form of isomerism in compounds containing at least one double bond where atoms or atomic groups attached to the doubly bound carbon atoms have no free rotation around the axis of the double bond. Geometric isomers with specific atomic groups on opposite sides of the double bond are called trans-isomers, while cis-isomers have those groups on the same side.

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isomerism

the possession by two or more distinct compounds of the same molecular formula, each molecule having the same number of atoms of each element, but in different arrangement.