摘要：AbstractHHe+is considered as the strongest acid and most powerful proton donor known to human. Whether HHe+exists at planetary high pressure environment is a quite important problem in physics, chemistry and planetary sciences. Here, using theab initioevolutionary algorithm USPEX package, we searched HF–He system, which was reported as the most possible candidate to contain HHe+. The calculation proved HHe+cannot form at pressure <1000 GPa, due to a conflict between the covalent component in symmetric hydrogen bond and ionic HHe+. Although He atoms have no chemical bonding with other elements, they can supply a chemical pressure, leading to two new phases He2(HF)4and He(HF). With coplanar (HF)4rings, He2(HF)4have an aromaticity-like electronic behavior while He(HF) has a new type of chiral HF chain. The formation of He2(HF)4and He(HF) prove that the chemical pressure from He, on par with external pressure, have ability to control the structural and electronic configuration and induce some new familiars of compounds include H and He elements which are fundamental planetary materials in giant planets.Graphical abstractDisplay OmittedHighlights•HHe+cannot exist at pressure <1000 GPa•With coplanar (HF)4rings, He2(HF)4have an aromaticity-like electronic behavior.
