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This work, titled Signature of low-dimensional quasi-F centers in zirconium- rich electrides, presents our newly discovered electride materials amongst zirconium-rich alloys, where non-nuclear interstitial anionic electrons (IAEs), or quasi-F centers, are trapped within the positively charged lattice framework. We utilized quantum mechanical density functional theory (DFT), implemented in the standard Vienna ab initio simulation package (VASP) software program, to investigate the localization of such IAEs within the lattice void spaces. Our electronic-structure calculations confirm the existence and stability of a one-dimensional distribution of localized IAEs interconnected with delocalized electron channels, which is different from other ordinary compounds. Because of their exotic electron-rich properties, electrides have become intriguing materials for a myriad of theoretical and experimental researchers, who seek to understand their unique technological applications in superconductivity, catalytic oxidation, electron emission, reversible hydrogen storage and non-linear optics, and as anode materials in batteries. Indeed, the discovery of electrides is a challenge, and they are still an under-explored class of materials, with only a few electrides being known to date. Herein, we identified novel electride members in Zr2X (X = O, Se, and Te) via several computational insights, which have not been reported yet in the literature. 

ABSTRACT Dippers are a common class of young variable star exhibiting day-long dimmings with depths of up to several tens of per cent. A standard explanation is that dippers host nearly edge-on (id ≈ 70°) protoplanetary discs that allow close-in (<1 au) dust lifted slightly out of the mid-plane to partially occult the star. The identification of a face-on dipper disc and growing evidence of inner disc misalignments brings this scenario into question. Thus, we uniformly (re)derive the inclinations of 24 dipper discs resolved with (sub-)mm interferometry from ALMA. We find that dipper disc inclinations are consistent with an isotropic distribution over id ≈ 0−75°, above which the occurrence rate declines (likely an observational selection effect due to optically thick disc mid-planes blocking their host stars). These findings indicate that the dipper phenomenon is unrelated to the outer (>10 au) disc resolved by ALMA and that inner disc misalignments may be common during the protoplanetary phase. More than one mechanism may contribute to the dipper phenomenon, including accretion-driven warps and ‘broken’ discs caused by inclined (sub-)stellar or planetary companions.