The first four-dimensional (4D) adiabatic potential energy surface (PES) for the interaction of NO+ cation with the H-2 molecule has been accurately determined using the CCSD(T)-F12a method with cc-pVTZ-F12 basis set augmented with mid-bond functions. A detailed characterization of the PES and lowest bound states of the H-2-NO+ complex have been provided. The H-2-NO+ PES exhibits a single global minimum with a well depth of 824.63 cm(-1) corresponding to off-planar structure with the H-2 molecule in a perpendicular orientation to the NO+ cation. The solution of the nuclear Schrodinger equation for the bound states gives a zero-point energy corrected dissociation energy of D-0 = 498.15 cm(-1) for para-H-2-NO+ complex, and of 541.35 cm(-1) for ortho-H-2-NO+.

}, keywords = {Bound states calculations, Potential energy surface}, issn = {0009-2614}, doi = {10.1016/j.cplett.2021.138511}, author = {Orek, Cahit and Uminski, Marcin and Klos, Jacek and Lique, Francois and Zuchowski, Piotr S. and Bulut, Niyazi} } @article { WOS:000692200800013, title = {Quantum Spin State Selectivity and Magnetic Tuning of Ultracold Chemical Reactions of Triplet Alkali-Metal Dimers with Alkali-Metal Atoms}, journal = {Phys. Rev. Lett.}, volume = {127}, number = {10}, year = {2021}, month = {AUG 31}, publisher = {AMER PHYSICAL SOC}, type = {Article}, abstract = {{We demonstrate that it is possible to efficiently control ultracold chemical reactions of alkali-metal atoms colliding with open-shell alkali-metal dimers in their metastable triplet states by choosing the internal hyperfine and rovibrational states of the reactants as well as by inducing magnetic Feshbach resonances with an external magnetic field. We base these conclusions on coupled-channel statistical calculations that include the effects of hyperfine contact and magnetic-field-induced Zeeman interactions on ultracold chemical reactions of hyperfine-resolved ground-state Na and the triplet NaLi(a(3)Sigma(+)) producing singlet Na-2((1)Sigma(+)(g)) and a Li atom. We find that the reaction rates are sensitive to the initial hyperfine states of the reactants. The chemical reaction of fully spin-polarized, high-spin states of rotationless NaLi(a(3)Sigma(+)}, issn = {0031-9007}, doi = {10.1103/PhysRevLett.127.103402}, author = {Hermsmeier, Rebekah and Klos, Jacek and Kotochigova, Svetlana and Tscherbul, Timur V.} } @article { WOS:000687394800001, title = {Relativistic aspects of orbital and magnetic anisotropies in the chemical bonding and structure of lanthanide molecules}, journal = {New J. Phys.}, volume = {23}, number = {8}, year = {2021}, month = {AUG}, publisher = {IOP PUBLISHING LTD}, type = {Article}, abstract = {The electronic structure of magnetic lanthanide atoms is fascinating from a fundamental perspective. They have electrons in a submerged open 4f shell lying beneath a filled 6s shell with strong relativistic correlations leading to a large magnetic moment and large electronic orbital angular momentum. This large angular momentum leads to strong anisotropies, i. e. orientation dependencies, in their mutual interactions. The long-ranged molecular anisotropies are crucial for proposals to use ultracold lanthanide atoms in spin-based quantum computers, the realization of exotic states in correlated matter, and the simulation of orbitronics found in magnetic technologies. Short-ranged interactions and bond formation among these atomic species have thus far not been well characterized. Efficient relativistic computations are required. Here, for the first time we theoretically determine the electronic and ro-vibrational states of heavy homonuclear lanthanide Er-2 and Tm-2 molecules by applying state-of-the-art relativistic methods. In spite of the complexity of their internal structure, we were able to obtain reliable spin-orbit and correlation-induced splittings between the 91 Er-2 and 36 Tm-2 electronic potentials dissociating to two ground-state atoms. A tensor analysis allows us to expand the potentials between the atoms in terms of a sum of seven spin-spin tensor operators simplifying future research. The strengths of the tensor operators as functions of atom separation are presented and relationships among the strengths, derived from the dispersive long-range interactions, are explained. Finally, low-lying spectroscopically relevant ro-vibrational energy levels are computed with coupled-channels calculations and analyzed.}, keywords = {lanthanide molecules, relativistic electronic structure, spin tensor decomposition, ultracold lanthanide atoms}, issn = {1367-2630}, doi = {10.1088/1367-2630/ac1a9a}, author = {Tiesinga, Eite and Klos, Jacek and Li, Ming and Petrov, Alexander and Kotochigova, Svetlana} } @article { WOS:000658822200035, title = {Roaming pathways and survival probability in real-time collisional dynamics of cold and controlled bialkali molecules}, journal = {Sci Rep}, volume = {11}, number = {1}, year = {2021}, month = {MAY 19}, publisher = {NATURE RESEARCH}, type = {Article}, abstract = {Perfectly controlled molecules are at the forefront of the quest to explore chemical reactivity at ultra low temperatures. Here, we investigate for the first time the formation of the long-lived intermediates in the time-dependent scattering of cold bialkali 23Na87Rb molecules with and without the presence of infrared trapping light. During the nearly 50 nanoseconds mean collision time of the intermediate complex, we observe unconventional roaming when for a few tens of picoseconds either NaRb or Na2 and Rb2 molecules with large relative separation are formed before returning to the four-atom complex. We also determine the likelihood of molecular loss when the trapping laser is present during the collision. We find that at a wavelength of 1064 nm the Na2Rb2 complex is quickly destroyed and thus that the 23Na87Rb molecules are rapidly lost.}, issn = {2045-2322}, doi = {10.1038/s41598-021-90004-0}, author = {Klos, Jacek and Guan, Qingze and Li, Hui and Li, Ming and Tiesinga, Eite and Kotochigova, Svetlana} } @article { WOS:000665117900005, title = {Universal stereodynamics of cold atom-molecule collisions in electric fields}, journal = {Phys. Rev. A}, volume = {103}, number = {6}, year = {2021}, month = {JUN 23}, publisher = {AMER PHYSICAL SOC}, type = {Article}, abstract = {We use numerically exact quantum dynamics calculations to demonstrate universal stereoselectivity of cold collisions of (2)Pi molecules with S-1-state atoms in an external electric field. We show that cold collisions of OH molecules in their low-field-seeking f-states, whose dipole moments are oriented against the field direction, are much more likely to lead to inelastic scattering than those of molecules oriented along the field direction, causing nearly perfect steric asymmetry in the inelastic collision cross sections. The universal nature of this effect is due to the threshold suppression of inelastic scattering between the degenerate +/- M Stark sublevels of the high-field-seeking e-state, where M is the projection of the total angular momentum of the molecule on the field axis. Above the Lambda-doublet threshold, the stereodynamics of inelastic atom-molecule collisions can be tuned via electric-field-induced resonances, which enable effective control of Ne + OH scattering over the range of collision energies achievable in current merged beam experiments.}, issn = {2469-9926}, doi = {10.1103/PhysRevA.103.062810}, author = {Tscherbul, V, Timur and Klos, Jacek} } @article { ISI:000568842200012, title = {Effects of conical intersections on hyperfine quenching of hydroxyl OH in collision with an ultracold Sr atom}, journal = {Sci Rep}, volume = {10}, number = {1}, year = {2020}, month = {AUG 24}, pages = {14130}, publisher = {NATURE PUBLISHING GROUP}, type = {Article}, abstract = {The effect of conical intersections (CIs) on electronic relaxation, transitions from excited states to ground states, is well studied, but their influence on hyperfine quenching in a reactant molecule is not known. Here, we report on ultracold collision dynamics of the hydroxyl free-radical OH with Sr atoms leading to quenching of OH hyperfine states. Our quantum-mechanical calculations of this process reveal that quenching is efficient due to anomalous molecular dynamics in the vicinity of the conical intersection at collinear geometry. We observe wide scattering resonance features in both elastic and inelastic rate coefficients at collision energies below k(B) x 10mK. They are identified as either p- or d-wave shape resonances. We also describe the electronic potentials relevant for these non-reactive collisions, their diabatization procedure, as well as the non-adiabatic coupling between the diabatic potentials near the CIs.}, issn = {2045-2322}, doi = {10.1038/s41598-020-71068-w}, author = {Li, Ming and Klos, Jacek and Petrov, Alexander and Li, Hui and Kotochigova, Svetlana} } @article {morita_full-dimensional_2020, title = {Full-dimensional quantum scattering calculations on ultracold atom-molecule collisions in magnetic fields: {The} role of molecular vibrations}, journal = {Phys. Rev. Res.}, volume = {2}, number = {4}, year = {2020}, note = {Place: ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA Publisher: AMER PHYSICAL SOC Type: Article}, abstract = {{Rigorous quantum scattering calculations on ultracold molecular collisions in external fields present an outstanding computational problem due to strongly anisotropic atom-molecule interactions that depend on the relative orientation of the collision partners, as well as on their vibrational degrees of freedom. Here, we present the first numerically exact three-dimensional quantum scattering calculations on strongly anisotropic atom-molecule (Li + CaH) collisions in an external magnetic field based on the parity-adapted total angular momentum representation and a new three-dimensional potential energy surface for the triplet Li-CaH collision complex developed using the unrestricted coupled-cluster method with single, double, and perturbative triple excitations and a large quadruple-zeta-type basis set. We find that while the full three-dimensional treatment is necessary for the accurate description of cold Li(M-S = 1/2) + CaH(v = 0}, doi = {10.1103/PhysRevResearch.2.043294}, author = {Morita, Masato and Klos, Jacek and Tscherbul, V, Timur} }