Roadmap on organic inorganic hybrid perovskite semiconductors and devices

Metal halide perovskites are the first solution processed semiconductors that can compete in their functionality with conventional semiconductors, such as silicon. Over the past several years, perovskite semiconductors have reported breakthroughs in various optoelectronic devices, such as solar cells, photodetectors, light emitting and memory devices, and so on. Until now, perovskite semiconductors face challenges regarding their stability, reproducibility, and toxicity. In this Roadmap, we combine the expertise of chemistry, physics, and device engineering from leading experts in the perovskite research community to focus on the fundamental material properties, the fabrication methods, characterization and photophysical properties, perovskite devices, and current challenges in this field. We develop a comprehensive overview of the current state of the art and offer readers an informed perspective of where this field is heading and what challenges we have to overcome to get to successful commercializatio

Millimeter-wave spectroscopy of HC5N in vibrationally excited states below 500 cm-1.

The rotational spectrum of the semistable HC5N molecule has been investigated in the millimeter-wave region for eight excited bending states which lie below 500 cm-1, namely $v_{11} =1,\,2,\,3$, and 4, $v_{10}=1$, $v_9=1$, ($v_{10} = 1$, $v_{11} = 1$), and ($v_{10} = 1$, $v_{11} = 2$). Transitions up to $J = 101 \leftarrow 100$ were measured, reaching a frequency as high as 270 GHz. The set of spectroscopic constants determined in the present work makes it possible to predict with much improved accuracy the transition frequencies of millimeter-wave lines produced by vibrationally excited HC5N in hot core molecular sources and circumstellar shells. In addition, results of extensive CCSD(T) calculations are presented, which yield accurate term values for low-lying bending vibrational states