Spectroscopic properties and radiative lifetimes of SiTe:A high-level multireference configuration interaction investigation

The 18 A-S states correlated to the lowest dissociation limit of SiTe were calculated by using a high-level multirefer-ence configuration interaction （MRCI） method, including scalar relativistic and spin-orbit coupling effects. Based on the calculated potential energy curves, the spectroscopic constants of bound states were determined, which are well consistent with previous experimental results. The spin-orbit matrix elements between the A-S states were computed, which lead to an in-deoth understanding, of oerturbations on the electronic state a^3∏. Finally. the transition dioole moments of allowed transitionsA^1∏-X^1∑^＋,E^1∑^＋-X^1∑^＋,a^3∏-d^3△,a^3∏-d^3△,a^∏-a′^3∑^＋,a^3∏-e^3∑^-,and the radiative lifetimes of A^1∏,E^1∑^＋,and a^3∏ were evaluated.     

Observation of large in-plane anisotropic transport in van der Waals semiconductor Nb2SiTe4

Two-dimensional (2D) van der Waals material is a focus of research for its widespread application in optoelectronics, memories, and spintronics. The ternary compound Nb₂SiTe₄ is a van der Waals semiconductor with excellent air stability and small cleavage energy, which is suitable for preparing a few layers counterpart to explore novel properties. Here, properties of bulk Nb₂SiTe₄ with large in-plane electrical anisotropy are demonstrated. It is found that hole carriers dominate at a temperature above 45 K with a carrier active energy of 31.3 meV. The carrier mobility measured at 100 K is about 213 cm²·V^-1·s^-1 in bulk Nb₂SiTe₄, higher than the reported results. In a thin flake Nb₂SiTe₄, the resistivity ratio between the crystalline axes of a and b is reaching about 47.3 at 2.5 K, indicating that there exists a large anisotropic transport behavior in their basal plane. These novel transport properties provide accurate information for modulating or utilizing Nb₂SiTe₄ for electronic device applications.     

Studies on rotational spectra of the ground states of ZnO,ZnS, SiSe and SiTe isotopic molecules using an isotopic error compensation approach

Accurate rotational spectra of 28 isotopologues of the ground electronic states of ZnO, ZnS, SiSe and SiTe are studied using an effective isotopic error compensation (IEC) approach. More than 200 new rotational transition frequencies are predicted for 20 of the above isotopologues using high-precision experimental data of the relevant isotopologues. The results show that the IEC approach can produce far more accurate rotational transition frequencies than the semi-classical isotope relation if the Born–Oppenheimer breakdown correction coefficients are ignored.     

Die Einstein-Rosen-Materie

The Einstein-Rosen matter is given by a space-time V₄ in which the domains z < 0 and z > 0 are isometric. But, on the hypersurface z = 0 the Riemannian tensor R_iklm and the Ricci tensor R_kl become delta-like infinite. On this surface the first derivations of the metric tensor g_ik have essential discontinuities. Therefore, it is impossible to cover the small domain –ε ≤ z ≤ +ε with one coordinate system of the class C₂.