NEW INFRARED EMISSION MEASUREMENTS ON HNC

Author Institution: Physikalisch-Chemisches Institut, Justus-Liebig-Universit\""{a}tWe have measured and analyzed the emission spectrum of HNC from 400 to $4100 cm^{-1}$. The HNC was observed as an equilibrium mixture of HCN and HNC in a fused quartz cell heated to 1350 K. The three fundamental bands and many hot bands of HNC were measured with resolutions ranging from $0.006 cm^{-1}$ for the lowest fundamental to $0.033 cm^{-1}$ for the other two. Thirty-five different vibrational and vibrational angular momentum states were measured. High rotational levels, in some cases up to $J = 50$, were also measured. Now all the quadratic contributions to the vibrational and rotational term values have been measured, as well as some higher order contributions

Simple molecules as complex systems

For individual molecules quantum mechanics (QM) offers a simple, natural and elegant way to build large-scale complex networks: quantized energy levels are the nodes, allowed transitions among the levels are the links, and transition intensities supply the weights. QM networks are intrinsic properties of molecules and they are characterized experimentally via spectroscopy; thus, realizations of QM networks are called spectroscopic networks (SN). As demonstrated for the rovibrational states of H2 16O, the molecule governing the greenhouse effect on earth through hundreds of millions of its spectroscopic transitions (links), both the measured and first-principles computed one-photon absorption SNs containing experimentally accessible transitions appear to have heavy-tailed degree distributions. The proposed novel view of high-resolution spectroscopy and the observed degree distributions have important implications: appearance of a core of highly interconnected hubs among the nodes, a generally disassortative connection preference, considerable robustness and error tolerance, and an â œ ultra-small-worldâ A property. The network-theoretical view of spectroscopy offers a data reduction facility via a minimum-weight spanning tree approach, which can assist high-resolution spectroscopists to improve the efficiency of the assignment of their measured spectra

The v(1) band system of H-CC-CN (cyanoacetylene)

The v(1) band system of cyanoacetylene (H-CC-CN) has been observed with an effective resolution of 0.006 cm(-1) v(1) = 3327.37085(3) cm(-1), B-1 = 0.15149762(2) cm(-1), D-1 = 1.8065(3) x 10(-8) cm(-1). Several hot bands from the states v(5) = 1, v(6) = 1, v(7) = 1, 2 (l = 0 and 2), 3 (l = 1 and 3), and 4 (l = 0 and 2), v(6) = v(7) = 1 (l = 0 and 2), and v(6) = 1 and v(7) = 2 (l = 3) have also been observed and analyzed. Many bands show strong local perturbations due to interactions with states which are combinations of the modes 4, 5, 6, and 7. These perturbing states are also described quantitatively, and rovibrational constants are given. (C) 1996 Academic Press, Inc