High resolution molecular beam study of the origin bands of the Ã 2Π–X̃ 2Σ+ and Ã″ 2Π1/2–X̃ 2Σ+ systems of yttrium imide (Y14NH, Y15NH, and Y14ND)

Abstract

The (0,0,0)–(0,0,0) bands of the à 2Π–X̃ 2Σ+ and Ã″ 2Π1/2–X̃ 2Σ+ systems of three isotopomers of yttrium imide (Y14NH, Y15NH, and Y14ND) have been studied by laser-induced fluorescence in a molecular beam apparatus. Rotational, fine, and nuclear magnetic hyperfine structures have been resolved and analyzed. The previously studied B̃ 2Σ+−X̃ 2Σ+ (0,0,0)–(0,0,0) bands of the three isotopomers have been reanalyzed. Global fits of all observed bands, in which the ground state has been fitted to a Hamiltonian model, while the excited states have been represented by term values, have been performed for the three isotopomers. Subsequently, the individual bands have been fitted. The ground state parameters have been fixed at the values obtained in the global fits, while the upper states have been fitted to the Hamiltonian models. The (0,0,0) à 2Π state of Y14NH, Y15NH, and Y14ND is severely perturbed. Even though the nature of these perturbing states can only be speculated upon, the introduction of effective perturbers made it possible to deperturb the state successfully. The Ã″ 2Π1/2 state is unperturbed. The spectra can be reproduced to better than 120 MHz (0.004 cm−1). The analyses confirm that the molecule is linear in all four states with the nuclear arrangement Y–N–H. The bond lengths (r0 structure) in the X̃ 2Σ+ ground state and the Ã″ 2Π1/2, à 2Π, and B̃ 2Σ+ excited states have been derived to be rYN=0.187785(17) nm, rNH=0.10039(14) nm; rYN=0.1927(1) nm, rNH=0.081(1) nm; rYN=0.19013(56) nm, rNH=0.1032(54) nm; and rYN=0.18848(52) nm, rNH=0.1236(46) nm, respectively. The electronic configurations for the X̃ 2Σ+ ground state and the à 2Π, Ã″ 2Π1/2, and B̃ 2Σ+ excited states are discussed and compared with ab initio calculations whenever possible.

Observation of the FeNC molecule by laser fluorescence excitation spectroscopy

“…4-6͒ and CuCl 2 . 7,8 In addition, high-resolution electronic spectra of the imides YNH and ScNH, [9][10][11][12] the methylidene VCH, 13 and the dicarbide YC 2 , 14 have also been reported. Despite the spectroscopic observation of a number of metal cyanide/isocyanide molecules, no such reports about transition-metal containing molecules of chemical formula MCN have previously been published.…”

Solvation of Yttrium with Ammonia: An Experimental and Theoretical Study

“…Six nonbonding NH 3 molecular orbitals are found: four orbitals at -0.45 au and two at -0.27 au. With three ammonia molecules, nine nonbonding NH 3 molecular orbitals are found (-0.45 and -0.27 au) while for YNH(NH 3 ) 4 12 nonbonding NH 3 molecular orbitals result. The energies of the nonbonding NH 3 molecular orbitals are quite similar for the four systems.…”

“…The binding arises from two counteracting contributions: electrostatic dipole-dipole interaction and dative interaction. 4 . This material is available free of charge via the Internet at http://pubs.acs.org.…”

“…It is known that yttrium imide is formed readily when ammonia is introduced in the plasma resulting from the laser vaporization of yttrium, but this may result from ion, excited states, or high-temperature chemistry. 3,4 Here, we demonstrate that indeed neutral yttrium atoms thermalized at 300 K react with ammonia to produce YNH. In addition, we show that further interactions with ammonia lead to the solvation of YNH rather than additional oxidative addition.…”

Fourier transform microwave spectroscopy of metal nitrides and imides: Quadrupole structure in ScN (X1Σ+), YN (X1Σ+), and BaNH (X∼1Zack1, Bucchino2, Binns3 et al. 2015Journal of Molecular Spectroscopy

“…Two classes of molecules are relevant in this regard: metal nitrides (MN) and metal imides (MNH). Although a variety of nitride and imide species have been investigated in the gas-phase spectroscopically, such as TiN, VN, CrN, MoN, ScNH, YNH and LaNH [4][5][6][7][8][9], few have been studied with sufficient resolution to examine their hyperfine structure. ScN, YN, and BaNH are three such species for which no hyperfine parameters are known.…”