B3Π State Research Articles

Theoretical re-investigation on the N–N bond breaking of N2O+ cations in the A2Σ+ and B2Π states at the CASPT2 level

Two-dimensional multistate potential energy surfaces along N–NO bond length and N–N–O bond angle of N2O+ in the A2Σ+ and B2Π states were calculated at the CASPT2/cc-pVQZ level. In comparison to the known decomposition mechanisms in linear structure, a new N–NO bond fission pathway was proposed in bent geometry for the A2Aʹ(A2Σ+) state with a lower barrier, leading to rotationally excited NO+(X1Σ+) and N(2D) fragments. Likewise, the respective contributions of the Aʹ and A″ components split from the B2Π state were clarified. Considering avoided crossing and the coupling of spin states, ro-vibrational distributions of the NO+ fragment ion observed in experiments are elucidated.

∧-type doublets and lifetime broadening in the B2Π–X2Π electronic origin band of C6H

We present a high-resolution study on the B2Π-X2Π electronic origin band spectrum of the C6H radical with its center at ~18990 cm-1 The C6H radicals are produced in a pulsed supersonic slit-jet discharge source and detected in direct absorption by sensitive cavity ring-down spectroscopy. By using a home-made narrow linewidth nanosecond pulsed laser source, the experimental spectrum allows to resolve the ∧-type doublet fine structures in high-J rotational lines. A set of improved B2Π state constants, including the ∧-type doubling parameters of p′ = −1.16(9)x10−3 cm−1q′ = -1.22(7)x10−4 cm−1 are determined from analysis of the experimental spectrum. An analysis on the spectral line profile has resulted in a significant linewidth broadening of ~0.05±0.01 cm−1, corresponding to a B2Π state lifetime of ~100±20 ps. The short lifetime of the excited B2Π state is proposed due to fast internal vibronic couplings to high-lying vibronic levels of lower electronic states.

Photoionization of the BeH molecule using R-matrix method

We investigated the photoionization from the X2Σ+ground state and the A2Π excited state of BeH using the R-matrix method with the close-coupling (CC) model. We used the configuration-interaction (CI) method to describe electronic correlation and the B-spline function to describe the continuum. We tested the calculated cross section with different partial waves and active spaces, and finally obtained the convergent results. The autoionization peaks near the ionization threshold are predicted for the first time. We detected two broad resonances with the photon energies around 16.1 and 18.0 eV at the geometry of the A2Π excited state. We reported the partial photoionization cross-sections and asymmetry parameters from the ground state of BeH to the X1Σ+, a3Σ+ and A1Σ+states of BeH+ions, together with the partial photoionization cross-sections from the A2Π excited state of BeH to the X1Σ+, b3Π and B1Π states of BeH+ions. Our predicted cross sections differ from the previously theoretical results from Pindzola et al. [J. Phys. B: At. Mol. Opt. Phys., 2019, 52, 195205] and Velasco et al. [Chem. Phys. Lett., 2008, 462, 344], both of which neglected correlation effects. The presented cross sections, along with the asymmetry parameter β for the angular distribution, are believed to be the most comprehensive and accurate dataset currently available for the BeH photoionization process at low energies.

Outer-valence ionization of nitrous oxide: A high-resolution electron momentum spectroscopy investigation

We report a detailed study on the outer-valence ionization of nitrous oxide (N2O) by a high-resolution (e, 2e) spectrometer employing asymmetric non-coplanar kinematics at an impact energy of 2500 eV. Binding energy spectrum in the energy region of 11–30 eV is obtained. Benefiting from the high energy resolution of 0.55 eV, four main peaks and six satellite structures are clearly identified in this region. The measured electron momentum profiles are compared with the theoretical calculations. Renner-Teller-effect induced geometry distortion is used to qualitatively interpret the observed discrepancy at low momentum between experiment and theory for B2Π state. The assignments and the pole strengths for these ionization states are determined by comparing the shape and the intensity of the experimental electron momentum profiles with those of the theoretical ones. In particular, two low-lying satellites at 21.0 eV and 27.1 eV are confirmed for the first time and attributed to the 2Π and 2Σ shake-up states. The present results show the evidence of strong electron correlation effects in the final states for the outer-valence ionization of N2O.

Fourier-transform spectroscopy and relativistic electronic structure calculation on the [formula omitted] state of KCs

The Ti:Saphire laser operated within 13800 - 11800 cm−1 range was used to excite the c3Σ+ state of KCs molecule directly from the ground X1Σ+ state. The laser-induced fluorescence (LIF) spectra of the c3Σ+→a3Σ+ transition were recorded with Fourier-transform spectrometer within 8000 to 10000 cm−1 range. Overall 673 rovibronic term values belonging to both e/f-components of the c3Σ+(Ω=1±) state of 39KCs, covering vibrational levels from v = 0 to about 45, and rotational levels J∈[11,149] were determined with the accuracy of about 0.01 cm−1; among them 7 values for 41KCs. The experimental term values with v∈[0,22] were involved in a direct point-wise potential reconstruction for the c3Σ+(Ω=1±) state, which takes into account the Ω-doubling effect caused by the spin-rotational interaction with the nearby c3Σ+(Ω=0−) state. The analysis and interpretation were facilitated by the fully-relativistic coupled cluster calculation of the potential energy curves for the B1Π, c3Σ+, and b3Π states, as well as of spin-forbidden c−X and spin-allowed c−a transition dipole moments; radiative lifetimes and vibronic branching ratios were calculated. A comparison of relative intensity distributions measured in vibrational c→a LIF progressions with their theoretical counterparts unambiguously confirms the vibrational assignment suggested in [J. Szczepkowski, et al., JQSRT, 204, 133–137 (2018)].

Transition properties of five lowest–lying singlet and three lowest–lying triplet states of silicon monosulphide molecule

The transition properties of the X1Σ+, C1Σ–, D1Δ, A1Π, E1Σ+, a3Σ+, d3Δ, and b3Π states of silicon monosulphide were investigated using the complete active space self-consistent field method, which was followed by the internally contracted multireference configuration interaction approach. The transition dipole moments were calculated for the dipole–allowed transitions between these singlet states and for all transitions between the X1Σ+, a3Σ+, d3Δ, and b3Π states. The radiative lifetimes of the first 16 vibrational levels were 107.6 – 120.5 ns for the A1Π state and 12.8 – 14.1 ns for the E1Σ+ state. Among these dipole–allowed transitions, the emissions from the A1Π – X1Σ+ and E1Σ+ – X1Σ+ systems were strong, whereas those from the b3Π – d3Δ system were weak. The radiative lifetimes of the first 16 levels were 4.3 – 9.8, 3.8 – 35.4, 2.2 – 7.9, and 11.9 – 14.5 ms for the a3Σ+1, a3Σ+0–, d3Δ1, and d3Δ2 states, respectively. These were 117 – 380, 73 – 581, and 137 – 586 μs for the b3Π0+, b3Π1, and b3Π2 states, respectively. Among these forbidden transitions, the b3Π0+ – X1Σ+0+ and b3Π1 – X1Σ+0+ transitions were the strongest. The Franck–Condon factors, Einstein A coefficients, and band origins of all these spontaneous emissions were calculated. The transition properties were compared with the available experimental and theoretical results.

Multiple Bonding in Rhodium Monoboride. Quasi-atomic Analyses of the Ground and Low-Lying Excited States.

The bonding structures of the ground state and the lowest five excited states of rhodium monoboride are identified by determining the quasi-atomic orbitals in full valence space MCSCF wave functions and the interactions between these orbitals. A quadruple bond, namely two π-bonds and two σ-bonds, is identified and characterized for the X1Σ+ ground state, in agreement with a previous report (Cheung J. Phys. Chem. Lett. 2020, 11, 659-663). However, in all excited states, the bonding is predicted to be weaker because, in these states, one of the σ-bonding interactions has a small magnitude. In the a3Δ and A1Δ states, the bond order is between a triple and quadruple bond. In the b3Σ+ state, the Rh-B linkage is a triple bond. In the c3Π and B1Π states, the atoms are linked by a double bond due to an additional weakening of the two π-bonds. The decreases in the predicted bond strengths are reflected in the decreases of the predicted binding energies and in the increases of the predicted bond lengths from the X1Σ+ ground state to the c3Π and the B1Π excited states. Notably, the 5pσ orbital of rhodium, which is vacant in the ground state of the atom, plays a significant role in the molecule.

Ab initio study of R-dependent behavior of the hyperfine structure parameters for the [formula omitted] states of LiRb and LiCs

Diagonal a3Σ1+-a3Σ1+ and off–diagonal X1Σ0++-a3Σ0-+ magnetic hyperfine structure (HFS) matrix elements were calculated ab initio for the LiRb and LiCs molecules in a wide range of internuclear distances using the multi–reference Fock space coupled clusters method with generalized relativistic effective core potentials to describe the four–component valence wavefunctions near the nuclei. At large distances, both HFS functions vary little, though they may fluctuate by as much as 12 to 24% in the intermediate range. The plateau exhibited by the a3Σ1+-a3Σ1+ HFS function at 4–5 Å, could be attributed to pronounced spin–orbit coupling of the intersecting a3Σ+ and b3Π states.

Radiative properties of the six lowest–lying triplet and four lowest–lying singlet states of boron nitride molecule

This study addresses the transition properties of the X3Π, A3Σ+, B3Σ–, C3Π, D3Π, E3Σ+, a1Σ+, b1Π, c1Δ, and d1Σ+ states of the boron nitride molecule. The potential energy curves and transition dipole moments are calculated using the complete active space self–consistent field method, followed by the valence internally contracted multireference configuration interaction approach. The radiative lifetimes are of the order of 10–8 s for the E3Σ+ state, 10–7–10–8 s for the C3Π state, 10–7 s for the D3Π and d1Σ+ states, 10–6 s for the c1Δ state, 10–5–10–6 s for the B3Σ– state, and 10–5 s for the A3Σ+ and b1Π states. The C3Π – X3Π and E3Σ– – X3Π transitions are strong, followed by the D3Π – X3Π, D3Π – B3Σ–, E3Σ– – A3Σ+, d1Σ+ – a1Σ+, and d1Σ+ – b1Π transitions. The spin–forbidden transitions from the a1Σ+ and b1Π states to the X3Π state are calculated and confirmed to be weak. The radiative lifetimes of all the vibrational levels are approximately 10–1 s for the a1Σ+0+ state. The contribution of the b1Π – X3Π transition to the radiative lifetimes of the b1Π state is sufficiently insignificant to be considered negligible. The Franck–Condon factors, Einstein A coefficients, and band origins of all the spontaneous vibronic emissions from all these transitions involved herein are calculated. The distribution of the radiative lifetime varying with rotational angular quantum number J is investigated at J ≤ 70 for a certain vibrational level υ of the A3Σ+, B3Σ–, C3Π, D3Π, E3Σ+, b1Π, and c1Δ states when υ ≤ 15. The transition properties reported in this study can provide useful guidelines for future investigations, both experimentally and theoretically.

Rotationally resolved optical-optical double resonance study of the f′ 0+ (1D2) ion-pair state of I35Cl

The f′ 0+ (1D2) ion-pair state of I35Cl, which correlates to the I+ (1D2) + Cl− (1S0) dissociation limit, was analyzed by an optical-optical double resonance scheme through the B3Π(0+) state as an intermediate state. In total, 442 transitions in the range of 2 ≤ vf′ ≤ 17, 13 ≤ Jf′ ≤ 50 were identified. Dunham coefficients for the f′ 0+ (1D2) ion-pair state were determined to be Y00 = 51200.42(13), Y10 = 160.599(50), Y20 = −0.1760(55), Y30 = −0.00216(18), Y01 = 0.05908(17), Y11 = −1.284(39) × 10−4, Y21 = −2.37(19) × 10−6, and Y02 = −3.198(16) × 10−8 cm−1. An RKR potential of the f′ 0+ (1D2) ion-pair state is constructed based on these constants.

Vibronic emissions and radiative lifetimes for a3Σ+, b3Π, c3Σ+, d3Δ, and e 3Σ– states of silicon monoxide

In this study, the potential energy curves of the a3Σ+, b3Π, c3Σ+, d3Δ, and e3Σ– states of the silicon monoxide are calculated and the transition dipole moments between them are computed using the complete active space self–consistent field, which is followed by the valence internally contracted multireference configuration interaction approach. The Davidson correction, core–valence correlation and scalar relativistic corrections are considered. The extrapolation of the potential energies to the complete basis set limit is included. The band origins, Einstein A coefficients, and Franck–Condon factors of all vibronic emissions between these five states are calculated. The rotationless radiative lifetimes are approximately 10–1 to 10–4 s for the b3Π state, 10–2 to 10–4 s for the d3Δ state, and 10–3 to 10–4 s for the e3Σ– state. The radiative lifetime quickly becomes shorter as the vibrational level increases for the three states. The lifetime is of the order of 100 ns for all vibrational levels of the c3Σ+ state, indicating that the spontaneous vibronic emissions originating from this state occurs easily. Overall, the vibronic emissions of the b3Π – a3Σ+, d3Δ – b3Π, and e3Σ– – b3Π systems are weak, suggesting that they are difficult to measure through spectroscopy. The vibronic emissions of the c3Σ+ – a3Σ+ and c3Σ+ – b3Π systems are strong, indicating that they are easy to measure in a spectroscopy experiment. The radiative lifetime with the variation of rotational angular momentum quantum number is discussed briefly for υ ≤ 15 and J ≤ 30 of the b3Π, c3Σ+, d3Δ, and e3Σ– states. The results indicate that the radiative lifetime changes only over a small range for each triplet state. The transition properties calculated in this study can be used to explain why only a few experimental transition properties are currently available for these triplet states.

N-loss photodissociation dynamics of N2O+(B2Π) near the NO+(Σ+1) + N(2P) dissociation limit.

Photodissociation dynamics of the N2O+ cation in its B2Π state has been experimentally studied in an energy region around the NO+(1Σ+) + N(2P) dissociation limit using a cryogenic cylindrical ion trap velocity map imaging spectrometer. The results show that the NO+(1Σ+) + N(2D) product channel dominates the dissociation dynamics and requires the NNO angle to change by 30°-50° prior to dissociation. The NO+(1Σ+) + N(2P) product channel, which directly correlates with the B2Π state but less competitive, opens immediately when the photon energy reaches the dissociation limits, indicating a flat dissociation pathway without bending on the B2Π state surface.

Vibronic emissions between the a1Σ+, b1Π, c1Δ, d1Σ+, e1Σ−, and f1Π states of the diatomic silicon carbide SiC

In recent years, emissions of silicon carbide molecule have been widely detected in carbon stars, stellar atmospheres, and interstellar molecular clouds. In order to evaluate the vibronic transitions between different singlet states of this molecule, we calculate the potential energy curves of the a1Σ+, b1Π, c1Δ, d1Σ+, e1Σ−, and f1Π states and compute the transition dipole moments between them. The band origins, Einstein A coefficients, and Franck–Condon factors of the vibronic emissions are computed for all possible transitions between these six lowest-lying states. Of these vibronic transitions, only the emissions of the d1Σ+–b1Π and f1Π–b1Π systems are strong. The emissions of the f1Π–a1Σ+ system are so weak that it is very difficult to measure them through spectroscopy. The rotationless radiative lifetimes are approximately several microseconds for all vibrational levels of the d1Σ+ and f1Π states, indicating that the vibronic emissions originating from the two states occur easily. The rotationless radiative lifetimes are approximately several ms for all vibrational levels of the e1Σ− state. Based on the Einstein A coefficients, we conclude that it is difficult to measure these emissions generated from the e1Σ− state, regardless of the radiative lifetime. The rotationless radiative lifetimes are of the order of 10−3–10−4 s for all vibrational levels of the b1Π and c1Δ states. The transition probabilities reported in this study can be employed to explain why the emissions between the singlet states of this molecule have rarely been measured to date, both in a spectroscopy experiment and in outer space.

Energy levels, transition dipole moment, transition probabilities and radiative lifetimes for low-lying electronic states of PN

The valence internally contracted multireference configuration-interaction (icMRCI) method is used to compute potential energy curves (PECs) of the X1Σ+, A1Π, C1Σ−, D1Δ, 21Π, a3Σ+, b3Π, d3Δ, e3Σ−, 23Δ, 23Σ−, 15Σ+ and 15Π states for PN, together with the Davidson, core-valence (CV) and scalar relativistic corrections, as well as the basis-set extrapolation. Transition dipole moments (TDMs) of fifteen dipole-allowed transitions between the thirteen states are calculated by the icMRCI approach with the aug-cc-pV6Z basis set. The vibrational band origins, Einstein coefficients and Franck-Condon factors of all spontaneous emissions for the fifteen band systems are determined, seeking to theoretically predict the strong emissions at least of the order of 103 s−1 for Einstein coefficients. Comparing with experimental measurements, our calculations can well reproduce the band origins and Franck-Condon factors of the A1Π-X1Σ+ system. Similar accuracy is assumed for the other band systems. Many emissions for the A1Π-X1Σ+, 21Π-A1Π, 21Π-X1Σ+, 21Π-C1Σ−, 21Π-D1Δ, b3Π-a3Σ+, e3Σ−-b3Π, 23Δ-13Δ, 23Σ−-13Σ−, 23Σ−-b3Π and 15Π-15Σ+ systems are found to be strong according to our calculated Einstein coefficients, whereas the emissions are weak for the 23Δ-b3Π system. Radiative lifetimes for the first 15 vibrational levels are evaluated to be about tens of nanoseconds for the 21Π state, about several hundred nanoseconds for the A1Π state, about several to tens of microseconds for the b3Π, 23Δ, 23Σ− and 15Π states and about several to several hundred microseconds for the e3Σ− state. The results can be used as guidelines for line identification and diagnostics of astrophysical plasma.

Transition probabilities of the seven lowest–lying singlet states of the AlN radical

In this study, the potential energy curves are calculated for the a1Σ+, b1Π, c1Δ, d1Σ+, e1Π, f1Δ, and g1Σ− states of the AlN radical. The transition dipole moments between them are computed. The rotationless radiative lifetimes of the vibrational levels are found to be approximately several µs for the d1Σ+ and g1Σ− states, on the order of several hundred ns for the e1Π state, and one-tenth to several µs for the deep well of the f1Δ state. These results suggest that the spontaneous emissions originated from these states occur readily. The rotationless radiative lifetimes of the vibrational levels are on the order of 10–100 µs for the c1Δ state, 1000 µs for the vdW minimum of the f1Δ state, and 10–1000 µs for the b1Π state. In addition, the rotationless radiative lifetimes of these states decrease with the increasing vibrational level. This result suggests that the spontaneous emissions generated from these states at lower levels should be difficult to occur. The Einstein coefficients of spontaneous emissions from the d1Σ+–a1Σ+, d1Σ+–b1Π, e1Π–a1Σ+, e1Π–b1Π, and g1Σ−–b1Π systems, as well as from the f1Δ state to the b1Π and c1Δ states are large, indicating that the emissions of these systems can be measured readily via spectroscopy. The Einstein coefficients of the e1Π–d1Σ+ transition are very small and the emissions originating from the vdW minimum of the f1Δ state are very weak, predicting that these transitions are very difficult to be detected in spectroscopy experiments.

Erratum: Approximate relativistic coupled-cluster calculations on heavy alkali-metal diatomics: Application to the spin-orbit-coupled A1Σ+ and b3Π states of RbCs and Cs2 [Phys. Rev. A 96 , 022516 (2017)

Erratum: Approximate relativistic coupled-cluster calculations on heavy alkali-metal diatomics: Application to the spin-orbit-coupled <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi mathvariant="bold-italic">A</mml:mi><mml:mspace width="0.16em" /><mml:mrow><mml:msup><mml:mrow /><mml:mn>1</mml:mn></mml:msup><mml:msup><mml:mi mathvariant="normal">Σ</mml:mi><mml:mo>+</mml:mo></mml:msup></mml:mrow></mml:mrow></mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi mathvariant="bold-italic">b</mml:mi><mml:mspace width="0.16em" /><mml:mrow><mml:msup><mml:mrow /><mml:mn>3</mml:mn></mml:msup><mml:mi mathvariant="normal">Π</mml:mi></mml:mrow></mml:mrow></mml:math> states of RbCs and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi mathvariant="bold">Cs</mml:mi><mml:mn mathvariant="bold">2</mml:mn></mml:msub></mml:math> [Phys. Rev. A <b>96</b> , 022516 (2017)

Approximate relativistic coupled-cluster calculations on heavy alkali-metal diatomics: Application to the spin-orbit-coupled A1Σ+ and b3Π states of RbCs and Cs2

Approximate relativistic coupled-cluster calculations on heavy alkali-metal diatomics: Application to the spin-orbit-coupled <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:mi>A</mml:mi><mml:mn>1</mml:mn></mml:msup><mml:msup><mml:mi mathvariant="normal">Σ</mml:mi><mml:mo>+</mml:mo></mml:msup></mml:mrow></mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:mi>b</mml:mi><mml:mn>3</mml:mn></mml:msup><mml:mi mathvariant="normal">Π</mml:mi></mml:mrow></mml:math> states of RbCs and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>Cs</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math>

NEW QUANTUM APPROACH TO DETERMINATION OF THE MOLECULAR SPECTRAL CONSTANTS AND PROBABILITIES FOR COOPERATIVE VIBRATIONROTATION-NUCLEAR TRANSITIONS IN SPECTRA OF DIATOMICS AND THE HADRONIC MOLECULES

It is proposed a new approach to construction of the potential function of diatomic molecules as a sum of the known perturbed Morse oscillator function, the Simons-Parr-Finlan molecular potential in the middle of the potential curve, function of the -Cn/Rn type at the large internuclear distances. Within this approach it is presented a precise scheme for computing the molecular spectral parameters, namely, vibrational, rotational, centrifugal constants for the electronic states of diatomics. As application it was carried out calculation of the of molecular constants (cm-1) for the X1Σ+ B1Π states of the KRb dimer and rubidium dimer and performed further comparison with experimental data. Within consistent approach to calculation of the electron-nuclear γ transition spectra (set of vibrationrotational satellites in molecule) of molecule there are obtained the estimates for vibration-rotationnuclear transition probabilities in a case of the emission and absorption spectrum of nucleus 127I(E(0)g = 203 keV) in the molecule of H127I for different approximations of the for potential curves: the hadmonic oscillator, the Dunham model and presented approach.

Accurate spectroscopic properties of 19 low-lying states of PCl radical including the electronic transition properties

The spectroscopic properties are in detail studied for the 11Σ−, 21Σ−, b1Σ+, c1Π, 21Π, 31Π, a1Δ, 21Δ, X3Σ−, C3Σ−, 33Σ−, 13Σ+, A3Π, B3Π, 33Π, 13Δ, 23Δ, 15Σ− and 15Π states, which are yielded from the first two dissociation limits, P(4Su)+Cl(2Pu) and P(2Du)+Cl(2Pu), of the PCl radical. Of the nineteen states, the 33Σ−, 13Σ+, 13Δ, 23Δ and 15Π states are the repulsive ones. The 21Σ−, 21Δ and 15Σ− states and the second well of A3Π state are very weakly-bound ones. The A3Π and B3Π states, the B3Π and 33Π states, and the 21Π and 31Π states have the avoided crossings. The A3Π state is found to possess the double well. The potential energy curves (PECs) are calculated with the CASSCF method followed by the internally contracted MRCI approach with Davidson correction together with the Dunning’s correlation-consistent basis sets, aug-cc-pV6Z. To improve the quality of PECs, core–valence correlation and scalar relativistic correction calculations are included simultaneously. The PECs are extrapolated to the complete basis set limit. The vibrational properties are evaluated for several weakly-bound states. The spectroscopic parameters are determined, and compared with those available in the literature. The Franck–Condon factors and radiative lifetimes of the transitions from the A3Π, B3Π and 33Π states to the X3Σ− state and from the c1Π, 21Π and 31Π states to the a1Δ state are calculated for several low vibrational states. And some necessary discussion is performed. Analyses demonstrate that the spectroscopic properties of PCl radical reported in this paper can be expected to be reliably predicted ones.

Time-, angle- and kinetic-energy-resolved photoelectron spectroscopy of highly excited states of NO

We investigate non-adiabatic dynamics of NO molecules that are photo-excited in the vacuum ultraviolet photon energy range using time-resolved velocity map imaging. Highly excited valence and Rydberg states are populated with a tunable (147–151 nm) femtosecond laser pulse and then ionized by a time-delayed near-IR laser pulse. Three main contributions are observed in the photoelectron kinetic spectra with corresponding electron yields that show pronounced oscillations. Two oscillations are assigned to ro-vibronic coupling in the valence-Rydberg mixture of the B and 4dδ N2Δ(v = 0) states and the B2Π(v = 25) and 4pπ K2Π(v = 1) states, respectively. We assign a third oscillation to originate from a coupling between two Rydberg states.