Rovibrational Line Lists of Triplet and Singlet Methylene.

The methylene molecule (CH) is a short-lived radical with lacking data on its spectral line intensities. Although the lifetime of CH is extremely short under Earth's conditions, it exists in a free form in interstellar media. CH is an important intermediate species in chemical reactions associated with the formation and destruction of complex hydrocarbons.

An Electrically Pumped Topological Polariton Laser.

With a seminal work of Raghu and Haldane in 2008, concepts of topology have been introduced into optical systems, where some of the most promising routes to an application are efficient and highly coherent topological lasers. While some attempts have been made to excite such structures electrically, the majority of published experiments use a form of laser excitation. In this paper, we use a lattice of vertical resonator polariton micropillars to form an exponentially localized topological Su-Schrieffer-Heeger defect.

A numerical-tensorial "hybrid" nuclear motion Hamiltonian and dipole moment operator for spectra calculation of polyatomic nonrigid molecules.

The analysis and modeling of high-resolution spectra of nonrigid molecules require a specific Hamiltonian and group-theoretical formulation that differs significantly from that of more familiar rigid systems. Within the framework of Hougen-Bunker-Johns (HBJ) theory, this paper is devoted to the construction of a nonrigid Hamiltonian based on a suitable combination of numerical calculations for the nonrigid part in conjunction with the irreducible tensor operator method for the rigid part. For the first time, a variational calculation from ab initio potential energy surfaces is performed using the HBJ kinetic energy operator built from vibrational, large-amplitude motion, and rotational tensor operators expressed in terms of curvilinear and normal coordinates.

Accurate ab initio potential energy surface, rovibrational energy levels and resonance interactions of triplet ( B ) methylene.

In this work, we report rovibrational energy levels for four isotopologues of methylene (CH , CHD, CD , and CH ) in their ground triplet electronic state ( B ) from variational calculation up to ~10,000 cm and using a new accurate ab initio potential energy surface (PES). Triplet methylene exhibits a large-amplitude bending vibration and can reach a quasilinear configuration due to its low barrier (~2000 cm ). To construct the ab initio PES, the Dunning's augmented correlation-consistent core-valence orbital basis sets were employed up to the sextuple-ζ quality [aug-cc-pCVXZ, X = T, Q, 5, and 6] combined with the single- and double-excitation unrestricted coupled cluster approach with a perturbative treatment of triple excitations [RHF-UCCSD(T)].