The status of nickelate superconductors in relation to cuprate high temperature superconductors is one of the concepts being discussed in high temperature superconductivity in correlated transition metal oxides. New additions to the class of infinite layer nickelates can provide essential input relating to connections or distinctions. A recently synthesized compound Ba_{2}NiO_{2}(AgSe)_{2}, which contains isolated ‘infinite layer’ NiO_{2}planes, may lead to new insights. Our investigations have discovered that, at density functional theory mean field level, the ground state consists of an unusual
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An electronic solid with itinerant carriers and localized magnetic moments represents a paradigmatic strongly correlated system. The electrical transport properties associated with the itinerant carriers, as they scatter off these local moments, have been scrutinized across a number of materials. Here, we analyze the transport characteristics associated with ultraclean PdCrO
 Award ID(s):
 2237522
 NSFPAR ID:
 10488361
 Publisher / Repository:
 Proceedings of the National Academy of Sciences of the United States of America
 Date Published:
 Journal Name:
 Proceedings of the National Academy of Sciences
 Volume:
 120
 Issue:
 36
 ISSN:
 00278424
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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Abstract singlet on the Ni^{2+}ion arising from large but separate Mott insulating gaps in both ${e}_{\mathrm{g}}$ orbitals, but with different, antiHund’s, spin directions of their moments. This textured singlet incorporates at the least new physics, and potentially a new platform for nickelate superconductivity, which might be of an unconventional form for transition metal oxides due to the unconventional undoped state. We include in this paper a comparison of electronic structure parameters of Ba_{2}NiO_{2}(AgSe)_{2}with a better characterized infinite layer nickelate LaNiO_{2}. We provide more analysis of the ${e}_{\mathrm{g}}$d ^{8}antiHund’s singlet that emerges in this compound, and consider a minimally correlated wavefunction for this singlet in an itinerant background, and begin discussion of excitations—real or virtual—that may figure into new electronic phases. 
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