The interaction between aqueous systems and an excess electron is of great interest. Here we study the planar water tetramer plus excess electron which is a illustrative model system. The model admits a bound anionic state in which the excess electron is in an extremely diffuse orbital. The description of this state requires the treatment of electron correlation; an uncorrelated Hartree-Fock treatment will not bind the electron. This system is a model for a larger class of systems known as nonvalence correlation bound (NVCB) anions. NVCB anions pose a challenge for computational methods given the need for an accurate treatment of electron correlation. Quantum Monte Carlo (QMC) methods are a family of accurate stochastic electronic structure methods. In this work, we explore the applicability of QMC methods to a model NVCB system and the impact of the trial wave function on the electron binding energy of this system. We present results from two different QMC methods: auxiliary field quantum Monte Carlo and diffusion Monte Carlo and compare them to standard" electronic structure methods such as equation of motion coupled cluster theory.

(H2O)<sub>4</sub><sup>-</sup>: Model nonvalence correlation bound anion system

Macromolecular Chemistry: The Second Century

[Author Benefits](https://scimeetings.acs.org/?utm_source=pubs_content_marketing&utm_medium=website&utm_campaign=0320_MCF_NPI_Launch_Spring_Homepage&ref=pubs_content_marketing)

[How to use SciMeetings](https://storage.googleapis.com/dl.morressier.com/acs/SciMeetings-ACSSpring2020-HowToGuide_M3020-Final.pdf)

[Frequently Asked Questions](https://storage.googleapis.com/dl.morressier.com/acs/SciMtng_ACSNMSp2020_FAQ_M3120_Final.pdf)

ACS Spring 2020 National Meeting & Expo

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.

(H2O)4-: Model nonvalence correlation bound anion system

(H2O)₄^-: Model nonvalence correlation bound anion system