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arXiv · 2206.08085

cRPA calculation of on-site and nearest neighbor Coulomb interaction of $LaNiO_2$

Long Zhang·Hai-Ping Cheng
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Abstract

We present first-principle calculation of the on-site and nearest neighbor Coulomb interaction strength of the Ni $d$ orbitals in bulk $LaNiO_{2}$, using the constrained Random Phase Approximation method. The nearest neighbor correlation within Ni-O plane turns out to be more significant when considering the frequency dependent $U(\omega)$, which can be as strong as about 25\% of the on-site value at medium and high frequencies. The inter Ni-O plane nearest neighbor correlation is found to be the same strength as that within the Ni-O plane, indicating the material is non-locally correlated also between the Ni-O planes.

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Long Zhang, Hai-Ping Cheng. 2022-06-16. cRPA calculation of on-site and nearest neighbor Coulomb interaction of $LaNiO_2$. https://arxiv.org/abs/2206.08085

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