A news article popped up in my newsfeed about a record in stability. This article shows that copper thyocianate can work as hole-transport material in a lead-based perovskite solar cell. They seem to achieve 1k-hour stability. Very promising indeed. Does lead have its days numbered?
Some of my work on the Runge-Gross theorem (the Hohenberg-Kohn theorem of TDDFT) was published this morning (JCP, 147, 134110). This theorem states that the time-dependent electronic density determines the potential uniquely (up to a constant), so we can define observables as time-dependent density-functionals. This manuscript extends the theorem to include time-dependent densities and potentials that are not Taylor expandable with respect to time. The Supp Info includes an alternative method, and an application to time-dependent current-density functional theory.