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The isoelectronic molecules UN and UO+ are known to have Ω = 3.5 and Ω = 4.5 ground states, respectively (where Ω is the unsigned projection of the electronic angular momentum along the internuclear axis). A ligand field theory model has been proposed to account for the difference [Matthew and Morse, J. Chem. Phys. 138, 184303 (2013)]. The ground state of UO+ arises from the U3+(5f3(4I4.5))O2− configuration. Owing to the higher nominal charge of the N3− ligand, the U3+ ion in UN is stabilized by promoting one of the 5f electrons to the more polarizable 7s orbital, reducing the repulsive interaction with the ligand and rendering U3+(5f27s(4H3.5))N3− the lowest energy configuration. In the present work, we have advanced the characterization of the UN ground state through studies of two electronic transitions, [18.35]4.5-X(1)3.5 and [18.63]4.5-X(1)3.5, using sub-Doppler laser excitation techniques with fluorescence detection. Spectra were recorded under field-free conditions and in the presence of static electric or magnetic fields. The ground state electric dipole moment [μ = 4.30(2) D] and magnetic ge-factor [2.160(9)] were determined from these data. These values were both consistent with the 5f27s configurational assignment. Dispersed fluorescence measurements were used to determine vibrational constants for the ground and first electronically excited states. Electric dipole moments and magnetic ge-factors are also reported for the higher-energy electronically excited states. [ABSTRACT FROM AUTHOR]

The odd isotopologues of ytterbium monohydroxide, 171,173YbOH, have been identified as promising molecules to measure parity (P) and time reversal (T) violating physics. Here, we characterize the A ̃ 2 Π 1 / 2 (0 , 0 , 0) − X ̃ 2 Σ + (0 , 0 , 0) band near 577 nm for these odd isotopologues. Both laser-induced fluorescence excitation spectra of a supersonic molecular beam sample and absorption spectra of a cryogenic buffer-gas cooled sample were recorded. In addition, a novel spectroscopic technique based on laser-enhanced chemical reactions is demonstrated and used in absorption measurements. This technique is especially powerful for disentangling congested spectra. An effective Hamiltonian model is used to extract the fine and hyperfine parameters for the A ̃ 2 Π 1 / 2 (0 , 0 , 0) and X ̃ 2 Σ + (0 , 0 , 0) states. A comparison of the determined X ̃ 2 Σ + (0 , 0 , 0) hyperfine parameters with recently predicted values [Denis et al., J. Chem. Phys. 152, 084303 (2020); K. Gaul and R. Berger, Phys. Rev. A 101, 012508 (2020); and Liu et al., J. Chem. Phys. 154,064110 (2021)] is made. The measured hyperfine parameters provide experimental confirmation of the computational methods used to compute the P,T-violating coupling constants Wd and WM, which correlate P,T-violating physics to P,T-violating energy shifts in the molecule. The dependence of the fine and hyperfine parameters of the A ̃ 2 Π 1 / 2 (0 , 0 , 0) and X ̃ 2 Σ + (0 , 0 , 0) states for all isotopologues of YbOH are discussed, and a comparison to isoelectronic YbF is made. [ABSTRACT FROM AUTHOR]

Properties of gas-phase thorium nitride, ThN, have been experimentally determined from a combined optical and microwave spectroscopic study. An intense band near 555 nm has been assigned as the [18.0]1.5–X2Σ+ (0,0) transition and recorded at high resolution in the presence of static electric and magnetic fields. The observed optical Stark shifts were analyzed to determine permanent electric dipole moments, μ → e l for the [18.0]1.5 and X2Σ+ states of 4.38 ± 0.02D and 5.11 ± 0.09D, respectively. Zeeman shifts were used to determine the magnetic g-factors. The pure rotational spectrum was recorded using a separated field optical pump/probe microwave repopulation scheme and analyzed to determine the bond length and 14N magnetic hyperfine and nuclear electric quadrupole parameters. A molecular orbital correlation diagram and ligand field electronic structure models are used to provide a qualitative interpretation of the electronic state ordering, magneto- and electro-static properties, and hyperfine interactions. Electronic structure calculations for the X2Σ+ state were performed, and results were compared with observations. Observed trends in μ → e l for the ThX (X = N, S, O, F, and Cl) series are discussed. [ABSTRACT FROM AUTHOR]

The laser-induced fluorescence excitation spectra of uranium monofluoride have been recorded in the range of 17000-19000 cm−1 using two-dimensional spectroscopy. High resolution dispersed fluorescence spectra and time-resolved fluorescence spectroscopy were also recorded. Three rotationally resolved bands were intensively analyzed, and all bands were found to be derived from the ground state X(1)4.5 with a rotational constant of 0.23421 cm−1. The low-lying electronic states were observed near 435 and 651 cm−1 in the dispersed fluorescence spectra, which were assigned as Ω′ = 3.5 and 2.5, respectively. The vibrational constants for the X(1)4.5 and X(1)3.5 states were calculated. The branching ratios of the dispersed fluorescence spectra for the [18.62]3.5, [17.72]4.5, and [17.65]4.5 states were reported. Radiative lifetime of 332(9) ns, 825(49) ns, and 433(15) ns for the [18.62]3.5, [17.72]4.5, and [17.65]4.5 states were obtained by fitting the time-resolved fluorescence spectroscopy, respectively. Transition dipole moments were performed using the branching ratios and the radiative lifetimes. [ABSTRACT FROM AUTHOR]

The [18.28]0--a³Δ1 (0,0) band near 647 nm of tantalum nitride, TaN, has been recorded and analyzed field-free and in the presence of static electric and magnetic fields. The fine and hyperfine parameters for the a³Δ1 and [18.28]0- states are determined. The 181Ta(I = 7/2) axial nuclear electric quadrupole coupling constant, eQq0, and the effective magnetic hyperfine coupling constant, h1, are used to garner insight into the nature of electronic states. The Stark tuning of the P(2) and Q(1) lines was analyzed to determine the molecular frame permanent electric dipole moment, →µel , for the a³Δ1 state of 4.49 ± 0.09 D. The Zeeman effect on the P(1) line was analyzed to determine an upper limit of the magnetic moment, →µm, for the a³Δ1 state. Scalar-relativistic coupled-cluster calculations for eQq0 and →µel of the a³Δ1 state are also reported and compared with experimental results. The determined properties are compared with the predicted values and the implication of the proposed scheme for determination of the 181Ta magnetic quadrupole moment is discussed. [ABSTRACT FROM AUTHOR]

The B2Σ- - X2Π3=2(0, 0) bands of a cold molecular beam sample of gold monoxide, AuO, and gold monosulfide, AuS, have been recorded at high resolution both field free and in the presence of a static electric field. The observed electric field induced splittings and shifts were analyzed to produce permanent electric dipole moments, μ⃗el , of 2.94 ± 0.06 D and 2.22 ± 0.05 D for theX2 Π3/2(v = 0) states ofAuOand AuS, respectively.Amolecular orbital correlation diagram is used to rationalize the trend in ground state μ⃗el values forAuX(X = F, Cl, O, and S) molecules. The experimentally determined μ⃗el are compared to those computed at the coupled-cluster singles and doubles (CCSD) level augmented with a perturbative inclusion of triple excitations (CCSD(T)) level of theory. [ABSTRACT FROM AUTHOR]

Singly deuterated silylene has been detected and characterized in the gas-phase using high-resolution, two-dimensional, optical spectroscopy. Rotationally resolved lines in the 000X¹A' → A¹A″ band are assigned to both c-type perpendicular transition and additional parallel, axis-switching induced bands. The extracted rotational constants were combined with those for SiH2 and SiD2 to determine an improved equilibrium bond length, rSiH, and bond angle, θ, of 1.5137 ± 0.0003 Å and 92.04? ± 0.05?, and 1.4853 ± 0.0005 Å and 122.48? ± 0.08? for the X¹A' (0,0,0) and A¹A″(0,0,0) state respectively. The dispersed fluorescence consists of a long progression in the A¹A″(0,0,0) →X¹A'(0,ν2,0) emission which was analyzed to produce vibrational parameters. A strong quantum level dependence of the rotationally resolved radiative decay curves is analyzed. [ABSTRACT FROM AUTHOR]

The (2,0) vibrational band of the A ² Σ - - X ²&#n;1055;1/2 transition of platinum nitride, PtN, was recorded at Doppler-limited resolution using intracavity laser absorption spectroscopy (ILS) and at sub-Doppler resolution using molecular beam laser induced fluorescence (LIF) spectroscopy. Isotopologue structure for 194PtN, 195PtN, and 196PtN, magnetic hyperfine splitting due to 195Pt (I = 2), and nuclear quadrupole splitting due to 14N (I = 1) were observed in the spectrum. Molecular constants for the ground and excited states are derived. The hyperfine interactions are used to illuminate the nature of the A ²Σ - excited electronic state. [ABSTRACT FROM AUTHOR]

The (0,0) A²Π-X²S+ band of a cold molecular beam sample of magnesium monodeuteride, MgD, has been recorded field-free and in the presence of a static electric field of up to 11 kV/cm. The lines associated with the lowest rotational levels are detected for the first time. The field-free spectrum was analyzed to produce an improved set of fine structure parameters for the A²Π (v = 0) state. The observed electric field induced splittings and shifts were analyzed to produce permanent electric dipole moments, μel 2.567D and 1.31D for A²Π (v = 0) and X²Σ+(v = 0) states, respectively. The recommended value for μelX²Σ+ (v = 0)) for MgH, based upon the measured value for MgD, is 1.32D. [ABSTRACT FROM AUTHOR]

High resolution spectra of the 0-0 band of the [18.6]3.5 - X(1)4.5 transition of uranium monofluoride, UF, obtained using a laser ablation spectrometer, showed a perturbation in the upper state. Examination of the Stark and Zeeman effects yielded permanent electric dipole moments of 2.01 and 1.88 D and magnetic g-factors of 3.28 and 3.26 for the ground and excited states, respectively. Both the dipole moment and g-factor of the ground state are in good agreement with ab initio calculations [I. O. Antonov and M. C. Heaven, J. Phys. Chem. A 117, 9684 (2013)]. The Zeeman effect results confirm that the ground state arises primarily from the U+(5f ³7s² 4I4.5)F- configuration and suggest several possible configurations for the upper state. [ABSTRACT FROM AUTHOR]

A number of low-rotational lines of the E4Δ7/2←X4Δ7/2 (1,0) band system of cobalt monoxide, CoO, were recorded field free and in the presence of a static electric field. The magnetic hyperfine parameter, h7/2, and the electron quadrupole parameter, eQq0, for the E4Δ7/2(υ = 1) state were optimized from the analysis of the field-free spectrum. The permanent electric dipole moment, ̄μel, for the X4Δ7/2 (υ = 0) and E4Δ7/2 (υ = 1) states were determined to be 4.18 ± 0.05 D and 3.28 ± 0.05 D, respectively, from the analysis of the observed Stark spectra of F' = 7←F" = 6 branch feature in the Q(7/2) line and the F' = 8←F" = 7 branch feature in the R(7/2) line. The measured dipole moments of CoO are compared to those from theoretical predictions and the trend across the 3d-metal monoxide series discussed. [ABSTRACT FROM AUTHOR]

Numerous rotational lines of the {18.26}1-X¹S+ band system of thorium sulfide, ThS, were recorded near 547.6 nm at a resolution of approximately 30 MHz. Measurements were made under field-free conditions, and in the presence of a static electric field. The field-free spectrum was analyzed to produce rotational and ?-doubling parameters. The Stark shifts induced by the electric field were analyzed to determine permanent electric dipole moments, µel, of 4.58(10) D and 6.72(5) D for the X¹S+ (v = 0) and {18.26}1 states, respectively. The results are compared with the predictions of previous and new electronic structure calculations for ThS, and the properties of isovalent ThO. [ABSTRACT FROM AUTHOR]

The (1,0) [17.9]2.5-X2Δ3/2 band of hafnium monofluoride (HfF) has been recorded using high-resolution laser-induced fluorescence spectroscopy both field-free and in the presence of a static electric field. The field-free spectra of 177HfF, 179HfF, and 180HfF were modeled to generate a set of fine and hyperfine parameter for the X2Δ3/2(v = 0) and [17.9]2.5 (v = 1) states. The observed optical Stark shifts for the 180HfF isotopologue were analyzed to produce the molecular frame electric dipole moments of 1.66(1) D and 0.419(7) D for the X2Δ3/2 and [17.9]2.5 state, respectively. Both the generalized effective core potential and all-electron four component approaches were used in ab initio calculations to predict the properties of ground state HfF including equilibrium distance, dipole moments, quadrupole coupling, and magnetic hyperfine constants. [ABSTRACT FROM AUTHOR]

The [11.9]Ω = 3/2 ← X 2Π3/2(0,0) and (1,0) bands of platinum monofluoride, PtF, have been recorded field-free and in the presence of a static electric field. The 19F(I = 1/2) and 195Pt(I = 1/2) magnetic hyperfine interactions have been analyzed and compared with predicted values obtained using atomic information and a proposed molecular orbital correlation diagram. The optical Stark shifts were analyzed to produce the permanent electric dipole moments, μvector el, of 2.47(11)D and 3.42(6)D for the [11.9]Ω = 3/2 and X 2Π3/2states, respectively. The observed trend in μvector el for the PtX (X = C,N,O,S and F) series is discussed and a comparison with IrF made. [ABSTRACT FROM AUTHOR]

We report the measurement of a jet-cooled electronic spectrum of the silicon trimer. Si3 was produced in a pulsed discharge of silane in argon, and the excitation spectrum examined in the 18 000-20 800 cm-1 region. A combination of resonant two-color two-photon ionization (R2C2PI) time-of-flight mass spectroscopy, laser-induced fluorescence/dispersed fluorescence, and equation-of-motion coupled-cluster calculations have been used to establish that the observed spectrum is dominated by the 13A1″ - ã 3A2′ transition of the D3h isomer. The spectrum has an origin transition at 18 600± 4 cm-1 and a short progression in the symmetric stretch with a frequency of ∼445 cm-1, in good agreement with a predicted vertical transition energy of 2.34 eV for excitation to the 13A1″ state, which has a calculated symmetric stretching frequency of 480 cm-1. In addition, a ∼505 cm-1 ground state vibrational frequency determined from sequence bands and dispersed fluorescence is in agreement with an earlier zero-electron kinetic energy study of the lowest D3h state and with theory. A weaker, overlapping band system with a ∼360 cm-1 progression, observed in the same mass channel (m/z = 84) by R2C2PI but under different discharge conditions, is thought to be due to transitions from the (more complicated) singlet C2v ground state (1A1) state of Si3. Evidence of emission to this latter state in the triplet dispersed fluorescence spectra suggests extensive mixing in the excited triplet and singlet manifolds. Prospects for further spectroscopic characterization of the singlet system and direct measurement of the energy separation between the lowest singlet and triplet states are discussed. [ABSTRACT FROM AUTHOR]

The laser induced fluorescence spectra of the 206Ã1A′′-X1A′ band of a rotationally cold (<20 K) molecular beam sample of chloro-methylene, HCCl, has been recorded, field-free and in the presence of a static electric field. The field-free spectrum has been analyzed to produce an improved set of spectroscopic parameters for the Ã1A′′ (060) vibronic state. The magnitude of the a-component of the permanent electric dipole moment, μa, for the X1A′ (000) vibronic state has been determined to be 0.501(1) D from the analysis of the observed electric field induced shifts. Comparisons with theoretical predictions and flouro-methylene, HCF, are presented. [ABSTRACT FROM AUTHOR]

The J = 1 → 2 pure rotational transitions in the X3Δ1(v = 0) state of 186W12C and 184W12C were recorded using a pump/probe microwave optical double resonance (PPMODR) technique and analyzed to give fine structure parameters. The field-free [17.6]2← X3Δ1 (1, 0) bands of the W13C isotopologues were recorded using laser induced fluorescence and analyzed to produce the 13C(I = 1/2) magnetic hyperfine parameter. Bonding in the [17.6]2(v = 1) and X3Δ1(v = 0) states is discussed and a comparison of the experimentally determined properties of the X3Δ1(v = 0) state with those predicted as a prelude to the electron electric dipole moment (eEDM) measurements [J. Lee, E. R. Meyer, R. Paudel, J. L. Bohn, and A. E. Leanhardt, J. Mod. Opt. 56, 2005 (2009)] is given. [ABSTRACT FROM AUTHOR]

The electronic spectrum of a cold molecular beam of zirconium dioxide, ZrO2, has been investigated using laser induced fluorescence (LIF) in the region from 17 000 cm-1 to 18 800 cm-1 and by mass-resolved resonance enhanced multi-photon ionization (REMPI) spectroscopy from 17 000 cm-1-21 000 cm-1. The LIF and REMPI spectra are assigned to progressions in the Ã1B2(ν1, ν2, ν3) ← X1A1(0, 0, 0) transitions. Dispersed fluorescence from 13 bands was recorded and analyzed to produce harmonic vibrational parameters for the X1A1 state of ω1 = 898(1) cm-1, ω2 = 287(2) cm-1, and ω3 = 808(3) cm-1. The observed transition frequencies of 45 bands in the LIF and REMPI spectra produce origin and harmonic vibrational parameters for the Ã1B2 state of Te = 16 307(8) cm-1, ω1 = 819(3) cm-1, ω2 = 149(3) cm-1, and ω3 = 518(4) cm-1. The spectra were modeled using a normal coordinate analysis and Franck-Condon factor predictions. The structures, harmonic vibrational frequencies, and the potential energies as a function of bending angle for the Ã1B2 and X1A1 states are predicted using time-dependent density functional theory, complete active space self-consistent field, and related first-principle calculations. A comparison with isovalent TiO2 is made. [ABSTRACT FROM AUTHOR]

Laser induced-fluorescence spectra of the 1-0 band of the A3[uppercase_phi_synonym]4 - X3[uppercase_phi_synonym]4 transition of iridium monofluoride, IrF, have been obtained at near natural linewidth resolution using supersonic molecular beam techniques. The spectra show a complex, clearly resolved hyperfine structure which has significant contributions from the magnetic and quadrupole hyperfine terms in 193Ir and 191Ir, both with I = 3/2, and the fluorine magnetic hyperfine term (I = 1/2). The spectra of both 193IrF and 191IrF isotopologues have been assigned and analyzed. The hyperfine structure was interpreted with the aid of atomic hyperfine parameters, which were used to determine the configurational composition of the ground state and to estimate the individual molecular hyperfine parameters. [ABSTRACT FROM AUTHOR]

The B1A′′(000)←X1A′(000) band system of a cold beam of CuOH has been studied field-free and in the presence of a static electric field. The Stark tuning of the low-J levels of the X1A′(000) state were analyzed to give a value of 3.968(32) D for the a-component of the permanent electric dipole moment, μa. An upper limit of 0.3 D for μa(B1A′′) is established from the lack of observable Stark tuning for the low-J levels of the B1A′′(000) state. The experimental value for μa(X1A′) is compared to theoretical predictions and other Cu-containing molecules. A molecular orbital correlation diagram is used to rationalize the large change in μa upon excitation. The electronegativity of OH was determined to be 2.81 from a comparison of the determined μa with the experimental μ values for CuF, CuO, and CuS. [ABSTRACT FROM AUTHOR]

The P(5) branch features of the A 3[uppercase_phi_synonym]4←X 3[uppercase_phi_synonym]4 (1,0) band near 628.2 nm of a molecular beam of iridium monofluoride, 193IrF, were recorded field free and in the presence of a static electric field. The 193Ir (I1=3/2) and 19F (I2=1/2) hyperfine interactions in the A 3[uppercase_phi_synonym]4 (υ=1) and X 3[uppercase_phi_synonym]4 (υ=0) states were analyzed. The permanent electric dipole moments, μvector el, for the A 3[uppercase_phi_synonym]4 (υ=1) and X 3[uppercase_phi_synonym]4 (υ=0) states were determined to be 1.88(5) and 2.82(6) D, respectively, from the analysis of the observed Stark shifts. A comparison of the electric dipole moments for IrC, IrN, and CoF is presented. [ABSTRACT FROM AUTHOR]

A number of low-J lines of the C 4Σ-←X 4Σ- (0,0) band of a supersonic molecular beam sample of vanadium monosulfide (VS) have been recorded at a resolution of approximately 50 MHz by laser excitation spectroscopy. The electric field induced shift and splitting have been analyzed to give the permanent electric dipole moments μ of the C 4Σ-(υ=0) and X 4Σ-(υ=0) states as 2.38(13) and 5.16(5) D, respectively. An electrostatic model is used to predict μ for VS and VO. A molecular orbital correlation diagram is used to rationalize the trends in experimentally observed μ values of the 3d-monosulfides and 3d-monoxides. A comparison with theoretical predictions is made. [ABSTRACT FROM AUTHOR]

A number of low-rotational lines of the A 2Σ-←X 2Π3/2(0,0) subband of a molecular beam of copper monoxide, CuO, were recorded field free and in the presence of a static electric field. A set of optimized fine and hyperfine parameters for the A 2Σ-(υ′=0) state was produced from the analysis of the field-free spectrum. The permanent electric dipole moments μ for the A 2Σ-(υ=0) and X 2Π3/2(υ=0) states were determined to be 1.12(71) and 4.57(3) D, respectively, from the analysis of the observed Stark shifts. The error of the experimentally determined μ value for the X 2Π3/2(υ=0) state is approximately ten times less than that for the previously determined value: μ=4.45(30) D [T. C. Steimle et al., J. Chem. Phys. 87, 5670 (1987)]. The experimental μ values are compared with theoretical predictions. [ABSTRACT FROM AUTHOR]

The low-rotational levels of the b 3Π-X 1∑+(0,0) band of copper monofluoride, CuF, were recorded field free and in the presence of a static electric field. The field-free spectrum was analyzed to produce a refined set of fine and hyperfine parameters for the b 3Π(v=0) state. The permanent electric dipole moment, μ, for the b 3Π(v=0) and X 1∑+(v=0) states were determined to be 2.36(2) and 5.26(2) D, respectively, from the analysis of the observed Stark shifts. The experimental μ values are compared to theoretical predictions. The change in μ upon excitation and the hyperfine parameters are discussed in terms of the proposed electronic configuration for the b 3Π and X 1∑+ states. The optical Stark spectroscopy of the A 2Π3/2-X 2∑+(0,0) subband of YO was also recorded and analyzed to precisely calibrate the electric field strength. The determined μ values are 3.714(5) and 4.542(40) D for the A 2Π3/2(v=0) and X 2∑+(v=0) states, respectively. [ABSTRACT FROM AUTHOR]

The optical Stark spectra of the R(4) and Q(4) lines of the [18.8]3[uppercase_phi_synonym]4-X 3[uppercase_phi_synonym]4(0,0) band systems of cobalt monofluoride, CoF, and the A′ 3[uppercase_phi_synonym]4-X 3[uppercase_phi_synonym]4(0,0) band systems of cobalt monohydride, CoH, have been recorded using laser induced fluorescence technique. The shifts and splittings caused by the static electric field have been analyzed to give the permanent electric dipole moments, μe, of 4.51(5) and 2.82(5) D for the [18.8]3[uppercase_phi_synonym]4 and X 3[uppercase_phi_synonym]4 states of CoF, and 0.01(8) and 1.88(8) D for the A′ 3[uppercase_phi_synonym]4 and X 3[uppercase_phi_synonym]4 states of CoH. The experimental dipole moments are compared with theoretical predictions. A molecular orbital correlation description is used to explain the relative ground state μe values for CoH and CoF. [ABSTRACT FROM AUTHOR]

The Zeeman tuning of the P1(0) line (ν=17 568.35 cm-1) of the A 7Π-X 7Σ+ (0,0) band of manganese monohydride, MnH, has been investigated. The laser induced fluorescence spectrum of a supersonic molecular beam sample was recorded at a resolution of approximately 40 MHz and with field strengths of up to 362.0 mT. The observed spectrum was successfully fitted using a traditional effective Zeeman Hamiltonian to determine an effective magnetic g-factor for the J=2 level of the F1-spin component of the A 7Π(v=0) state. Spectral predictions of the P1(0) line at field strengths used in magnetic trapping experiments are presented. [ABSTRACT FROM AUTHOR]

Stark and Zeeman spectra of the [16.7]3-X4 transition of neodymium monoxide (NdO) have been obtained at a resolution of less than 40 MHz. Analysis of the Stark spectra yielded permanent electric dipole moments μel of 3.742(16) and 3.369(13) D for the [16.7]3 and X4 states, respectively. The ground state value μel is compared to that of isovalent uranium monoxide (UO) and those of other lanthanide monoxides using a molecular orbital description. Analysis of the Zeeman spectra yielded magnetic ge factors of 2.084(6) and 2.178(8) for the J=3 and 4 rotational levels, respectively, of the [16.7]3 state and a ge factor of 2.116(6) for the X4 state. A comparison with the ge factor expected from the ab initio [Allouche et al., J. Chem. Phys. 124, 184317 (2006)] and the ligand field theory [P. Carette and A. Hocquet, J. Mol. Spectrosc. 131, 301 (1988)] predictions for the X4 ground state is given. [ABSTRACT FROM AUTHOR]

The sub-Doppler laser induced fluorescence spectra of numerous branch features in the B 2Σ+-X 2Σ+(0,0) band of calcium monodeuteride were recorded field-free and in the presence of a static electric field of up to 7 kV/cm. The field-free spectra were analyzed to produce an improved set of fine structure parameters for the B 2Σ+(v=0) state. The observed electric field induced splittings and shifts were analyzed to produce permanent electric dipole moments of 2.57(3) and 2.51(3) D for B 2Σ+(v=0) and X 2Σ+(v=0) states, respectively. The permanent electric dipole moment for the X 2Σ+(v=0) state of CaH is estimated to be 2.53(3) D. [ABSTRACT FROM AUTHOR]

The fine and hyperfine interaction parameters in the A 2Π1/2(v=0) and X 2Σ+(v=0) states of the odd metal nuclear spin isotopologues of ytterbium monofluoride, 171YbF and 173YbF, have been determined from an analysis of high-resolution laser induced fluorescence spectra of the A 2Π1/2←X 2Σ+(0,0) band. The observed ground X 2Σ+(v=0) state 171Yb(I=1/2) Fermi contact parameter is significantly smaller than that determined from the matrix isolation electron spin resonance measurement [Van Zee et al., J. Phys. Chem. 82, 1192 (1978)]. An interpretation of the 173,171Yb magnetic hyperfine and nuclear electric quadrupole coupling parameters is given. [ABSTRACT FROM AUTHOR]

A number of low-N lines of the X 6Σ+←A 6Σ+(0,0) band of chromium monodeuteride, CrD, have been recorded at near the natural linewidth limit by high resolution laser excitation spectroscopy of a supersonic molecular beam sample. The shifts and splitting of these lines caused by a static electric field have been analyzed to give the permanent electric dipole moments of the X 6Σ+(υ=0) and A 6Σ+(υ=0) states as 3.510(33) and 1.153(3) D, respectively. The dipole moment of the A 6Σ+(υ=0) state can be measured with higher precision because of some interesting near degeneracies in its level structure. The trends in the observed dipole moments for the first-row transition metal monohydrides are rationalized and compared with theoretical predictions. [ABSTRACT FROM AUTHOR]

Factors responsible for the undesirably high values of positive-channel (p-channel) threshold voltage (Vt) in high-κ metal oxide semiconductor transistors are investigated. In silicon/silicon dioxide/hafnium dioxide/metal gate transistors an anomalous nonlinear relationship between the equivalent oxide thickness (EOT) and Vt occurs when the silicon dioxide (SiO2) interface layer is sufficiently thin (<2.3 nm). The deviation from the expected EOT versus Vt behavior is shown to be related to processing temperature, metal work-function, substrate doping type, and thickness of the high-κ material. This result, coupled with charge trapping measurements on samples with different SiO2 interface layer thickness, suggests that the loss of negative fixed charge via the tunneling of trapped electrons to the substrate is a possible explanation for the elevated p-channel Vt. [ABSTRACT FROM AUTHOR]

High resolution optical spectroscopy has been used to study a molecular beam of molybdenum monocarbide (MoC). The Stark effect of the Re(0) and Qfe(1) branch features of the [18.6] 3Π1-X 3Σ-(0,0) band system of 98MoC were analyzed to determine the permanent electric dipole moments μe of 2.68(2) and 6.07(18) D for the [18.6] 3Π1(ν=0) and X 3Σ-(ν=0) states, respectively. The dipole moments are compared with the experimental value for ruthenium monocarbide [T. C. Steimle et al., J. Chem. Phys. 118, 2620 (2003)] and with theoretical predictions. A molecular orbital correlation diagram is used to interpret the observed and predicted trends of ground state μe values for the 4d-metal monocarbides series. [ABSTRACT FROM AUTHOR]

The optical Stark effect in the RR13(0.5) branch feature of the [18.1] 2Π1/2-X 4Σ1/2- (v′,v″=0) band of rhodium monosulfide (RhS) has been recorded and analyzed to determine the permanent electric dipole moment μe of 3.40(2) D for the ground X 4Σ1/2- (v=0) state and an upper limit of 1.5 D for the [18.1] 2Π1/2 state. Molecular orbital correlation diagrams are used to interpret the relative values of μe for RhN, RhO, and RhS. The 103Rh(I=1/2) magnetic hyperfine interaction in the X 4Σ1/2- and [18.1] 2Π1/2 states is analyzed. [ABSTRACT FROM AUTHOR]

The optical Stark effect in the Q(1) and R(0) lines of the [15.1]1-X 1Σ+ (1,0) band of rhodium mononitride (RhN) were recorded and analyzed to determine the permanent electric dipole moments μ for the X 1Σ+(υ=0) and [15.1]1(υ=1) states to be 2.43(5) and 1.75(1) D, respectively. The determined dipole moments are compared to predicted values obtained from density functional theory [Stevens et al., Chem. Phys. Lett. 421, 281 (2006)] and an all-electron ab initio calculation [Shim et al., J. Mol. Struct. THEOCHEM 393, 127 (1997)]. A simple single configuration molecular orbital correlation diagram is used to rationalize the relative values of μ for the 4d mononitrides and RhO. An electronic configuration for the [15.1]1 state is proposed based on the interpretation of the 103Rh and 14N magnetic hyperfine interactions. [ABSTRACT FROM AUTHOR]

The SR11(0) and SR11(1) branch features of the [15.8] and [16.0]2Π1/2-X 4Σ- (0,0) subband systems of rhodium monoxide, RhO, have been studied at near the natural linewidth limit of resolution by optical Stark spectroscopy using laser induced fluorescence detection. The Stark shifts and splittings were analyzed to produce the magnitude of the permanent electric dipole moment, |μ|, of 3.81(2) D for the X 4Σ3/2- (v=0) state. The results are compared to density functional theory calculations. Trends in observed values of |μ| across the 4d series of transition metal monoxides are interpreted in terms of simple single configuration molecular orbital correlation diagrams. [ABSTRACT FROM AUTHOR]

Permanent electric dipole moments and magnetic g factors for uranium monoxide (UO) have been determined from analyses of optical Stark and Zeeman spectra recorded at a spectral resolution that approaches the natural linewidth limit. Numerous branch features in the previously characterized [L. A. Kaledin et al., J. Mol. Spectrosc. 164, 27 (1994)] (0,0) [18403]5-X(1)4 and (0,0) [18404]5-X(1)4 electronic transitions were recorded in the presence of tunable static electric (Stark effect) or magnetic (Zeeman effect) fields. The lines exhibited unusually large Zeeman tuning effects. A ligand field model and an ab initio electronic structure calculation [R. Tyagi, Ph.D. thesis, The Ohio State University (2005)] were used to interpret the ground state properties. The results indicate that the low energy electronic states of UO are sufficiently ionic for the meaningful application of ligand field theory models. The dipole moments and g factors were distinctly different for the three electronic states examined, which implies that these properties may be used to deduce the underlying electronic state configurations. [ABSTRACT FROM AUTHOR]

The fine and hyperfine interaction parameters in the [18.8] 3[uppercase_phi_synonym] (υ=0) and X 3[uppercase_phi_synonym] (υ=0) states of cobalt monofluoride, CoF, have been determined from an analysis of high-resolution laser induced fluorescence spectra of the [18.8] 3[uppercase_phi_synonym]3-X 3[uppercase_phi_synonym]3 and [18.8] 3[uppercase_phi_synonym]4-X 3[uppercase_phi_synonym]4 band systems. The previously reported pure rotational transitions of the X 3[uppercase_phi_synonym]4(υ=0) state [T. Okabayashi and M. Tanimoto, J. Mol. Spectrosc. 221, 149 (2003)] were included in the data set. The hyperfine parameters for 59Co (I=7/2) and 19F (I=1/2) have been interpreted using atomic data together with a proposed molecular orbital description for the [18.8]3[uppercase_phi_synonym]i and X 3[uppercase_phi_synonym]i states. A comparison of the hyperfine parameters in the X 3[uppercase_phi_synonym] state of cobalt monohydride, CoH, with those of the X 3[uppercase_phi_synonym] state of CoF reveals that the bonding in the two molecules is significantly different. It is shown that, in a situation where the Ω substates of a multiplet degenerate electronic state are analyzed separately, the Fermi contact parameter b can be determined with fair accuracy from the apparent centrifugal distortion of the hyperfine structure. [ABSTRACT FROM AUTHOR]

A supersonic molecular beam of iron monohydride, FeH, has been generated using a laser ablation/chemical reaction scheme and probed at near-natural linewidth resolution by optical Stark spectroscopy utilizing laser-induced fluorescence detection. The observed Stark splitting in Q(3.5) and R(3.5) lines of the F 4Δ7/2←X 4Δ7/2 (1,0) transition were analyzed to determine values for the magnitudes of the permanent electric dipole moments, |μ|, which were found to be 2.63(3) and 1.29(3) D for the X 4Δ (v=0) and F 4Δ (v=1) states, respectively. A comparison with ab initio theoretical predictions is made. The Λ doubling in the low-J levels of the F 4Δ7/2 (v=1) state is also modeled. [ABSTRACT FROM AUTHOR]

Ruthenium monofluoride, RuF, has been detected using low-resolution laser-induced fluorescence (LIF) in the visible and near infrared spectral regions. A visible band, designated as [18.2]5.5-X 4[uppercase_phi_synonym]9/2, has been recorded field-free and in the presence of a static electric field using high-resolution LIF spectroscopy. The r0 internuclear distances for the [18.2]5.5 and X 4[uppercase_phi_synonym]9/2 states were determined to be 1.911 and 1.916 Å, respectively. The vibrational interval ΔG1/2 of 534(15) cm-1 for the X 4[uppercase_phi_synonym]9/2 state was determined from the analysis of the dispersed LIF. The Stark shifts of the visible band were analyzed to produce permanent electric dipole moments of 1.97(8) and 5.34(7) D for the [18.2]5.5 and X 4[uppercase_phi_synonym]9/2, states, respectively. The fluorine magnetic hyperfine structure associated with spectral features was analyzed. The hyperfine structure and dipole moments are interpreted using a molecular-orbital correlation model and compared with FeF and other ruthenium-containing molecules. [ABSTRACT FROM AUTHOR]

The Q(4) and R(4) branch features of the (0,0)D 5Δ4-X 5Δ4 band system and the Q(3) and R(3) branch features of the (0,0)D 5Δ3-X 5Δ3 band system of iron monoxide FeO have been studied by optical Stark spectroscopy. The Stark splittings in the high resolution laser induced fluorescence spectra were analyzed to produce values for the magnitude of the permanent electric dipole moments |μ| of 4.50±0.03, 4.29±0.05, 2.53±0.04, and 2.58±0.06 D for the X 5Δ4 (v=0), X 5Δ3 (v=0), D 5Δ4 (v=0), and D 5Δ3 (v=0) states, respectively. The results are compared to several ab initio predictions and to FeC. The qualitative trends are explained in terms of a molecular orbital correlation picture. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The high-resolution laser induced fluorescence spectra of tungsten mononitride WN and rhenium mononitride ReN have been recorded in a laser ablation/molecular beam spectrometer. The field free spectrum of the (0,0)A 4Π3/2-X 4Σ1/2- band system of 186WN has been analyzed to produce B″, B′, and γ″ values of 0.4659(2), 0.4554(2), and 0.0518(1) cm-1, respectively. The permanent electric dipole moments μ for the X 4Σ1/2- and A 4Π3/2 state were determined to be 3.77(18) and 2.45(3) D, respectively, from the analysis of the optical Stark effect. The (0,0)[26.0]0+-X0+ band system of ReN was recorded in the presence of a variable static electric field. The ground and excited state electric dipole moments of 187ReN were determined to be μ(X0+)=1.96(8) D and μ([26.0]0+)=3.53(4) D. Splittings in the field free 187ReN spectrum were analyzed to produce 187Re (I=5/2) nuclear electric quadrupole coupling constants e2Qq0 of -0.0304(8) and 0.0328(9) cm-1 for the X0+ and [26.0]0+ states, respectively. A molecular orbital correlation model is used to interpret the observation and a comparison is made to CrN and MoN. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Numerous branch features in the (0,0) A 2Π-X 2Σ+ band system of calcium monohydride CaH have been studied by optical Stark spectroscopy. The Stark shifts, Stark splittings, and appearance of electric-field-induced transitions in the high resolution laser-induced fluorescence spectra are analyzed to produce values for the magnitude of the permanent electric dipole moments |μ| of 2.94(16) D and 2.372(12) D for the X 2Σ+(v=0) and A 2Π(v=0) states, respectively. A comparison with values predicted from a semiempirical electrostatic model and previous ab initio calculations for |μ| (X 2Σ+) is presented. The change in |μ| upon excitation from the X 2Σ+ state to the A 2Π state is rationalized using a simple molecular orbital description. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The low rotational features of the (0,0) F [sup 2]Σ[sup +]←X [sup 2]Σ[sup +] band system of a supersonic molecular beam of RuN have been recorded at high spectral resolution via laser induced fluorescence spectroscopy. The electric field induced dependence of the P[sub 11](1) and [sup R]Q[sub 21](0) branch features of the [sup 104]RuN isotopomer were analyzed to produce permanent electric dipole moments, μ, of 1.89(5) and 1.07(5) D for the X [sup 2]Σ[sup +] and F [sup 2]Σ[sup +] states, respectively. The splitting in the field free spectrum of the [sup 101]RuN isotopomer was analyzed to produce a Fermi contact, b[sub F](X [sup 2]Σ[sup +]), parameter of -0.0349(4) cm-1. The results are interpreted using the electronic structure predictions for the F [sup 2]Σ[sup +] and X [sup 2]Σ[sup +] states given by Ram et al. [J. Chem. Phys. 109, 6329 (1998)] and compared with RuC and FeC. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The [18.1]¹Π ← X ¹Σ[sup +] band system of a molecular beam sample of RuC has been recorded field free and in the presence of a static electric field using high resolution laser induced fluorescence spectroscopy. The Stark shifts of the optical features for the [sup 102]RuC isotopomer were analyzed to produce permanent electric dipole moments of 3.31(4) and 4.09(14) D for the [18.1]¹Π and X¹Σ[sup +] states, respectively. The hyperfine structure associated with spectral features for the [sup 101]RuC and [sup 99]RuC isotopomers was analyzed to produce electric quadrupole and magnetic hyperfine coupling parameters. The hyperfine structure and dipole moments are interpreted using a molecular orbital correlation model and compared with predictions from electronic structure calculations and isovalent iron monocarbide, FeC. [ABSTRACT FROM AUTHOR]

The optical Stark effect has been measured for the &Btilde; ²Σ[sup +] - &Xmacr; ²Σ[sup +], 3[sub 0]¹, and 2[sub 0]¹(P' = 3/2) bands of lanthanum imide, LaNH, prepared in a supersonic molecular beam. The permanent electric dipole moment, μ, for the &Xtilde;²Σ[sup +] state was determined to be 2.53 ± 0.06 D from measurements of the second-order Stark shifts in the &Btilde; ²Σ[sup +] - &Xtilde;²Σ[sup +], 3[sub 0]¹ band. (ν[sub 3] is the La-N stretching vibration, of symmetry σ[sup +].) The dipole moment in the &Btilde; ²Σ[sup +] state is too small to be determined from the Stark shifts in this band, but could be determined from the first-order Stark splittings in the P' = 3/2 component of the B ²Σ[sup +], 2¹ bending fundamental (of upper state π symmetry); it was found to be 0.3 ± 0.2 D. A comparison is made with LaO and other isovalent molecules involving Group IIIA atoms. [ABSTRACT FROM AUTHOR]

Numerous branch features in the (0,0) [12.0] Ω=2←X³Λ[sub 3] and (0,0) [13.1] ³Φ[sub 4] ←X³A[sub 3] band systems of the iron monocarbide, FeC, have been studied using optical Stark spectroscopy. The electric field induced splittings in the high resolution laser induced fluorescence spectra were analyzed to produce values for the permanent electric dipole moments, μ, of 4.02(6) D, 4.44(6) D, and 2.36(3) D for the [12.0] Ω=2, [13.1] ³Φ[sub 4], and X³Λ[sub 3] states, respectively. A comparison with other iron containing molecules and theoretical predictions is made. [ABSTRACT FROM AUTHOR]

The optical Stark effect in the (0,0) A ²Π[sub 3/2]-X²Σ[sup +], A²Π[sub ½]-X²Σ[sup +], and B ²Sigma;[sup +] - X²Σ[sup +] band systems of a lanthanum monoxide, LaO, supersonic molecular beam sample have been analyzed to produce permanent dipole moments, μ, for the A ²Π[sub 3/2], A ²Π[sub ½], and B ²Σ[sup +] states of 1.89(6) D, 2.44(2) D, and 0.2(1) D, respectively. Fine structure splitting in the field free A ²Π[sub 3/2]-X²Σ[sup +] and A ²Π[sub ½]-X²Σ[sup +] spectra were analyzed to produce the magnetic hyperfine spectroscopic parameters a = 233(4) MHz, c = -261(12) MHz, and d = 410(4) MHz. A comparison with other group IIIA monoxides is made. [ABSTRACT FROM AUTHOR]

Studies laser-induced fluorescence and Optical/Stark spectroscopy of platinum monocarbide. Field free high resolution laser-induced fluorescence; Band rotational analysis; Nuclear spin rotation parameters; Dipole moments.

Studies the pure rotational transitions of radicals using a pump/probe microwave-optical double resonance (PPMODR) technique from which the hyperfine parameters of nitrogen were precisely determined. Insight into the nature of the electronic wave functions of the metal mononitrides from the analysis of the magnetic hyperfine interactions.