Triplet states in siloxene and porous silicon

Zero-field optically detected magnetic resonance (Zf-ODMR) investigations have revealed a broad distribution of the fine structure constants in crystalline siloxene and in porous silicon attributed to a broad distribution of triplet states in both materials. By time-resolved ODMR, a triplet emission (phosphorescence) can be identified. The electronic triplet energy and the spin-spin separation distance of the triplet spins are correlated via the decay times of time-resolved optical and ODMR spectroscopy. The light emitting states, the lowest triplet and the associated single state, have molecular character. A possible charge transfer character of the triplet state is discussed.