Will tetrahedral [ZnABCD]2+ display optical isomerism?

If carbon, with ABCD groups attached, shows optical isomerism (a non-racemic mixture at least) then shouldn't a non-racemic mixture of this compound show it too?

No, tetrahedral [ZnABCD]2+ does not display optical isomerism. Optical isomerism occurs in compounds that have a chiral center, which means they have four different groups attached to a central atom. In a tetrahedral complex, such as [ZnABCD]2+, the central metal ion (Zn) and the surrounding ligands (A, B, C, and D) are arranged in a tetrahedral geometry, meaning they are all bonded to the central atom in a symmetrical manner. As a result, there is no chiral center or asymmetric carbon present, and therefore no optical isomerism.

To determine whether a tetrahedral complex like [ZnABCD]2+ displays optical isomerism, we need to examine its molecular structure and analyze the presence of chirality.

Optical isomerism, also known as enantiomerism, occurs when two molecules are non-superimposable mirror images of each other. In other words, they have the same connectivity of atoms but cannot be aligned perfectly in 3D space. Chirality is the property that gives rise to optical isomerism.

In a tetrahedral complex, such as [ZnABCD]2+, the geometry around the central metal ion is tetrahedral (with four ligands). To determine the presence of optical isomerism, we need to check if the tetrahedral complex is chiral or achiral.

A tetrahedral complex is achiral if it possesses a symmetry element known as a plane of symmetry or a center of inversion. These elements will cause the molecule to be superimposable on its mirror image, thereby making it achiral. On the other hand, the absence of a plane of symmetry or a center of inversion makes the tetrahedral complex chiral.

Now, to determine whether [ZnABCD]2+ is chiral or achiral, we need to know the identity of ligands A, B, C, and D. If any of these ligands are different, it increases the possibility of chirality. However, if all four ligands are the same, the complex will be symmetric and achiral.

So, the presence of optical isomerism in [ZnABCD]2+ depends on the specific ligands surrounding the central zinc ion. Analyzing the ligands and determining whether they are different or symmetric will give you the answer to the question.