More Like this

1. Language + Molecules

   https://doi.org/10.18653/v1/2024.eacl-tutorials.3  

   Edwards, Carl; Wang, Qingyun; Ji, Heng (January 2024, Association for Computational Linguistics)
2. Heteronuclear Rydberg molecules

   https://doi.org/10.1103/PhysRevA.101.060701  

   Whalen, J. D.; Kanungo, S. K.; Lu, Y.; Yoshida, S.; Burgdörfer, J.; Dunning, F. B.; Killian, T. C. (June 2020, Physical Review A)

   null (Ed.)
3. Electrostatically embedded molecules‐in‐molecules approach and its application to molecular clusters

   https://doi.org/10.1002/jcc.26492  

   Tripathy, Vikrant; Saha, Arjun; Raghavachari, Krishnan (February 2021, Journal of Computational Chemistry)

   Abstract We report the application of our fragment‐based quantum chemistry model MIM (Molecules‐In‐Molecules) with electrostatic embedding. The method is termed “EE‐MIM (ElectrostaticallyEmbeddedMolecules‐In‐Molecules)” and accounts for the missing electrostatic interactions in the subsystems resulting from fragmentation. Point charges placed at the atomic positions are used to represent the interaction of each subsystem with the rest of the molecule with minimal increase in the computational cost. We have carefully calibrated this model on a range of different sizes of clusters containing up to 57 water molecules. The fragmentation methods have been applied with the goal of reproducing the unfragmented total energy at the MP2/6‐311G(d,p) level. Comparative analysis has been carried out between MIM and EE‐MIM to gauge the impact of electrostatic embedding. Performance of several different parameters such as the type of charge and levels of fragmentation are analyzed for the prediction of absolute energies. The use of background charges in subsystem calculations improves the performance of both one‐ and two‐layer MIM while it is noticeably important in the case of one‐layer MIM. Embedded charges for two‐layer MIM are obtained from a full system calculation at the low‐level. For one‐layer MIM, in the absence of a full system calculation, two different types of embedded charges, namely, Geometry dependent (GD) and geometry independent (GI) charges, are used. A self‐consistent procedure is employed to obtain GD charges. We have further tested our method on challenging charged systems with stronger intermolecular interactions, namely, protonated ammonia clusters (containing up to 30 ammonia molecules). The observations are similar to water clusters with improved performance using embedded charges. Overall, the performance of NPA charges as embedded charges is found to be the best. 

   more » « less
4. Bootstrap Embedding for Molecules

   https://doi.org/10.1021/acs.jctc.9b00529  

   Ye, Hong-Zhou; Ricke, Nathan D.; Tran, Henry K.; Van Voorhis, Troy (June 2019, Journal of Chemical Theory and Computation)
5. Ultralong-range Rydberg molecules

   https://doi.org/10.1088/1361-6455/ad7459  

   Dunning, F_B; Kanungo, S_K; Yoshida, S. (October 2024, Journal of Physics B: Atomic, Molecular and Optical Physics)

   Abstract Ultralong-range Rydberg molecules (ULRMs) comprise a Rydberg atom in whose electron cloud are embedded one (or more) ground-state atoms that are weakly-bound through their scattering of the Rydberg electron. The existence of such novel molecular species was first predicted theoretically in 2000 but they were not observed in the laboratory until 2009. Since that time, interest in their chemical properties, physical characteristics, and applications has increased dramatically. We discuss here recent advances in the study of ULRMs. These have yielded a wealth of information regarding low-energy electron scattering in an energy regime difficult to access using alternate techniques, and have provided a valuable probe of non-local spatial correlations in quantum gases elucidating the effects of quantum statistics. Studies in dense environments, where the Rydberg electron cloud can enclose hundreds, or even thousands, of ground-state atoms, have revealed many-body effects such as the creation of Rydberg polarons. The production of overlapping clouds of different cold atoms has enabled the creation of heteronuclear ULRMs. Indeed, the wide variety of atomic and molecular species that can now be cooled promises, through the careful choice of atomic (or molecular) species, to enable the production of ULRMs with properties tailored to meet a variety of different needs and applications. 

   more » « less