Slashdot

They likely mean it has (or rather, would have) the same structure as the fictional kryptonite (based on nomenclature). Similar compounds usually share some characteristics such as reactivity (e.g. all alkali metals react with water in a similar fashion but with differeing severity), melting point, etc.

That assumption does not typically hold for complicated compounds with so many elements. For one, there are frequently many different possible crystal structures for the same molecule which exist under different conditions, which may have significantly different structures and properties. Additionally, there are often different molecular structures allowed for different formulae (called isomers), which often have drastically different properties. Additionally, the fictional and real versions differ in that the fictional contained fluorine, a very chemically active element that tends to drastically alter the properties of anything with which it bonds for a variety of interesting reasons.

So ultimately, it would be impossible to suggest that they would share the same properties based on similar but not identical chemical formulae, and that might not hold even if they were identical. As such, the press release is nothing more than some jackass wanting his 15 minutes.