Higher Dimensional V Si Spacetimes

We present the explicit metric forms for higher dimensional vanishing scalar invariant (V SI) Lorentzian spacetimes. We note that all of the V SI spacetimes belong to the higher dimensional Kundt class. We determine all of the V SI spacetimes which admit a covariantly constant null vector, and we note that in general in higher dimensions these spacetimes are of Ricci type III and Weyl type III. The Ricci type N subclass is related to the chiral null models and includes the relativistic gyratons and the higher dimensional ppwave spacetimes. The spacetimes under investigation are of particular interest since they are solutions of supergravity or superstring theory. [PACS: 04.20.Jb, 04.65+l]