Software for the frontiers of quantum chemistry:An overview of developments in the Q-Chem 5 package

This article summarizes technical advances contained in the fifth major release of the Q-Chem quantum chemistry program package, covering developments since 2015. A comprehensive library of exchange–correlation functionals, along with a suite of correlated many-body methods, continues to be a hallmark of the Q-Chem software. The many-body methods include novel variants of both coupled-cluster and configuration-interaction approaches along with methods based on the algebraic diagrammatic construction and variational reduced density-matrix methods. Methods highlighted in Q-Chem 5 include a suite of tools for modeling core-level spectroscopy, methods for describing metastable resonances, methods for computing vibronic spectra, the nuclear–electronic orbital method, and several different energy decomposition analysis techniques. High-performance capabilities including multithreaded parallelism and support for calculations on graphics processing units are described. Q-Chem boasts a community of well over 100 active academic developers, and the continuing evolution of the software is supported by an “open teamware” model and an increasingly modular design

Ecological contrasts across an Antarctic land-sea interface

We report the composition of terrestrial, intertidal and shallow sublittoral faunal communities at sites around Rothera Research Station, Adelaide Island, Antarctic Peninsula. We examined primary hypotheses that the marine environment will have considerably higher species richness, biomass and abundance than the terrestrial, and that both will be greater than that found in the intertidal. We also compared ages and sizes of individuals of selected marine taxa between intertidal and subtidal zones to test the hypothesis that animals in a more stressed environment (intertidal) would be smaller and shorter lived. Species richness of intertidal and subtidal communities was found to be similar, with considerable overlap in composition. However, terrestrial communities showed no overlap with the intertidal, differing from previous reports, particularly from further north on the Antarctic Peninsula and Scotia Arc. Faunal biomass was variable but highest in the sublittoral. While terrestrial communities were depauperate with low biomass they displayed the highest overall abundance, with a mean of over 3 × 105 individuals per square metre. No significant differences in ages of intertidal and subtidal individuals of the same species were found, with bryozoan colonies of up to 4 years of age being present in the intertidal. In contrast with expectation and the limited existing literature we conclude that, while the Antarctic intertidal zone is clearly a suboptimal and highly stressful habitat, its faunal community can be well established and relatively diverse, and is not limited to short-term opportunists or waifs and strays

Phyllocarid crustaceans from the Upper Devonian Gogo Formation, Western Australia

Phyllocarids (Crustacea: Malacostraca) from the Upper Devonian (Givetian-Frasnian) Gogo Formation of Western Australia are described and two new species are reconstructed. The mineralized exoskeleton is well preserved in concretions, but the appendages, apart from the mandible, are unknown. Montecaris gogoensis sp. nov. (Echinocarididae) is represented by > 600 specimens; a possible second species of Montecaris is represented only by similar to 14 specimens of antero-dorsal fragments of the valves, which are highly tuberculate. Schugurocaris wami sp. nov. (Ceratiocarididae) is represented by > 300 specimens; a possible second species with a very elongate telson is represented by four specimens. An undetermined species of Dithyrocaris (Dithyrocarididae) is represented by > 80 specimen