Here's why:

* S4 is a formula, not a name. It represents a molecule containing four sulfur atoms.

* Sulfur can form various allotropes. This means that different arrangements of sulfur atoms can lead to different compounds with varying properties.

* There are multiple possible structures for S4. For example, tetrasulfur (S4) can exist in a cyclic (S4 ring) or a chain-like structure.

Therefore, to give a specific name to S4, you would need to specify the particular structure of the compound.

For example:

* Tetrasulfur (S4 ring): This refers to the cyclic form of S4.

* Tetrasulfur chain: This refers to the chain-like form of S4.

Without further context about the structure, S4 is simply a formula representing a molecule containing four sulfur atoms.