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Updated: Jan 13, 2026

Site Directed Spin Labeling and EPR Spectroscopic Studies of Pentameric Ligand-Gated Ion Channels

Site Directed Spin Labeling and EPR Spectroscopic Studies of Pentameric Ligand-Gated Ion Channels

Published on: July 4, 2016

EOM-DEA-CCSDおよびEOM-DIP-CCSDの解析勾配：理論、実装、およびラジカルへの応用

Tingting Zhao¹, Anna I Krylov¹

¹Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA.

The Journal of chemical physics

|January 7, 2026

Abstract:

Equation-of-motion coupled-cluster theory with single and double excitations (EOM-CCSD) provides a robust framework for describing a wide range of electronically excited and open-shell states. Among its various formulations, the double electron-attachment (EOM-DEA-CCSD) and double ionization potential (EOM-DIP-CCSD) methods are particularly effective for treating diradicals and other types of open-shell species. To enable accurate geometry optimizations and property calculations, we present the derivation and implementation of analytic nuclear gradients for EOM-DEA-CCSD and EOM-DIP-CCSD. These new capabilities were illustrated by calculations of singlet-triplet gaps in benzyne diradicals as well as characterization of molecules relevant to quantum information science. We further extended the framework to include spin-orbit coupling calculations for EOM-DEA-CCSD states, allowing calculations of intensity borrowing and intersystem crossings.

キーワード:

解析勾配方程式運動クラスター法開殻系ラジカル量子情報科学

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