The crystalline solid BaTiS 3 (barium titanium sulfide) is terrible at conducting heat, and it turns out that a wayward titanium atom that exists in two places at the same time is to blame. The ...

The titanium atom existing in two places at the same time gives rise to what is known as a "two-level system." In this case, the titanium atom has two states: a ground state and an excited state.

Figure 1. (a) Distribution of a butterfly-shaped 3d electron orbital. (b) Valence electron density distribution around the titanium (Ti3+) ion at the centre of the titanium oxide (TiO6 ...