Abstract. This paper presents SunPy (version 0.5), a community-developed Python package for solar physics. Python, a free, cross-platform, general-purpose, highlevel programming language, has seen widespread adoption among the scientific community, resulting in the availability of a large number of software packages,

The analysis of echolocation calls and mitochondrial DNA sequences recently revealed the existence of two cryptic bat species in Western Europe which were regarded as 'Pipistrellus pipistrellus' for more than 200 years. We now present data on acoustic and genetic characters across Europe including a novel genetic marker from the nuclear genome. Intraspecific variation of end frequencies of echolocation calls did not differ between geographic regions and only a little overlap existed between the two species. Nuclear and mitochondrial DNA sequences for the two species were highly divergent. No evidence was found for additional cryptic species in this group. With the exception of Scandinavia, both species occur across the whole of Europe and largely overlap in their range. The distribution of the species using echolocation calls at higher frequencies extends further north and the same species is also more common in the south along the Mediterranean Sea.

In the present article, an evaluation of different approaches for estimating the electronic coupling and charge-transport parameters in organic semiconductors is provided. As a testbed for that comparison, the α-polymorph of quinacridone is chosen. This system is particularly well suited for the purpose, as α-quinacridone intermolecular interactions in distinct crystallographic directions are dominated by the three mechanisms most relevant in organic semiconductors: π-stacking, H-bonding, and van der Waals stacking. Density-functional theory-based simulations yield a comparably complex band structure, which provides the means for demonstrating shortcomings of commonly applied approaches. These include the estimation of transport properties based on bandwidths and the calculation of electronic transfer integrals considering molecular dimers. As a particularly promising alternative, the fitting of suitably complex tight-binding models to the DFT-calculated bands in the entire Brillouin zone is proposed. These fits bear the advantage of directly producing intermolecular coupling constants for all relevant neighboring molecules as input parameters for hopping and dynamic disorder models. They also yield an analytic expression for the electronic bands. These allow the extraction of parameters relevant for band-transport models (like group velocities and effective masses) in the entire Brillouin zone.Here ε is the on-site energy, t the transfer integral between neighboring units, and a is the real space distance between the lattice

Organic semiconductors, charge-carrier mobilities, machine learning, tight-binding, transfer integrals, effective masses 2 A crucial factor determining charge transport in organic semiconductors is the electronic coupling between the molecular constituents, which is heavily influenced by the relative arrangement of the molecules. This renders quinacridone, with its multiple, structurally fundamentally different polymorphs and their rich, diverse intermolecular interactions an ideal testcase for analyzing the correlation between the electronic coupling in a specific configuration and its energetic stability. To provide an in-depth analysis of this relation, starting from the -polymorph of quinacridone, we also construct a coplanar model crystal. This allows us to systematically compare the displacement-dependence of the electronic coupling with that of the total energy. In this way, we identify the combination of exchange repulsion and electrostatic interactions as driving force steering the system towards a structure in which the electronic coupling is minimal, especially for the valence band. Such a situation can be avoided by either increasing the magnitude of the displacement or by displacements along the short molecular axis, where either the correlation between valence-band width and total energy is lifted, or where the minima in total energy become so shallow that even minor structural modifications have the potential to boost the electronic coupling. The general character of these observations is supported by equivalent trends for an analogous pentacene model system. Thus, the presented data can be regarded as the basis for analyzing the interplay between electronic coupling and energetic stability in crystalline organic semiconductors, which makes them a useful starting point for the future design of materials with improved properties.3

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