Rotationally Resolved State-to-State Photoelectron Study of Molybdenum Monoxide Cation (MoO+)

Zhihong Luo; Yih-Chung Chang; Yi Pan; Kai-Chung Lau; C. Y. Ng

doi:10.1021/acs.jpca.5b07939

Rotationally Resolved State-to-State Photoelectron Study of Molybdenum Monoxide Cation (MoO⁺)

Zhihong Luo, Yih-Chung Chang, Yi Pan, Kai-Chung Lau^*, C. Y. Ng^*

^*Corresponding author for this work

Research output: Journal Publications and Reviews › RGC 21 - Publication in refereed journal › peer-review

19 Citations (Scopus)

Abstract

By employing the two-color visible-ultraviolet (vis-UV) laser pulsed field ionization-photoelectron (PFI-PE) measurement, we have obtained rotationally selected and resolved photoelectron spectra for the MoO⁺(X⁴∑^- v⁺ = 0, 1, and 2) and MoO⁺(a²Δ_3/2,5/2; v⁺ = 0 and 1) cationic states. The unambiguous rotational assignments have made possible the determination of highly precise values for the band origin v00⁺ = 60 147.9 ± 0.8 cm^-1, rotation constant B₀⁺ = 0.4546 ± 0.0006 cm^-1, spin-spin coupling constant λ = 26.454 ± 0.017 cm^-1, and bond length r_e⁺ = 1.642 ± 0.001 Å for the MoO⁺(X⁴∑^-) ground state; v00⁺ = 60 556.4 ± 0.8 cm^-1, B₀⁺ = 0.4711 ± 0.0005 cm^-1, and r₀⁺ = 1.613 ± 0.001 Å for the MoO⁺ (a²Δ_3/2) excited state; and v00⁺ = 61 718.2 ± 0.8 cm^-1, B₀⁺ = 0.4695 ± 0.0006 cm^-1, and r₀⁺ = 1.616 ± 0.001 Å for the MoO⁺ (a²Δ_5/2) excited state. The ionization energy (IE) for MoO is determined to be IE(MoO) = 60 095.1 ± 0.8 cm^-1 [7.4508 ± 0.0001 eV]. Furthermore, the vibrational constants are determined as ω_e⁺ = 1000 ± 9 cm^-1 and ω_e⁺x_e⁺ = 5 ± 3 cm^-1 for MoO⁺(X⁴∑^-); the vibration spacing ΔG(1/2) for MoO⁺(a²Δ_3/2) is also measured as 1065 ± 4 cm^-1. On the basis of the thermochemical cycle, together with the known IE(Mo) and the IE(MoO) determined in this study, the difference of 0 K bond dissociation energy for MoO⁺ and that for MoO is determined to be D₀(Mo⁺-O) - D₀(Mo-O) = IE(Mo) - IE(MoO) = -2890.8 ± 0.9 cm^-1 [-0.3584 ± 0.0001 eV]. The energetic and spectroscopic values determined here have been used for benchmarking calculations at the CCSDTQ/CBS level of theory. The CCSDTQ/CBS predictions, IE(MoO) = 7.457 eV, r_e⁺ = 1.651 Å, ω_e⁺ = 974 cm^-1, D₀(Mo-O) = 5.386, and D₀(Mo⁺-O) = 5.015 eV, are found to be in good agreement with the vis-UV PFI-PE measurements. We also recommend a set of equally reliable CCSDTQ/CBS thermochemical values for MoO and MoO⁺: ΔH°_f0(MoO) = 383.7, ΔH°_f298(MoO) = 384.0, ΔH°_f0(MoO⁺) = 1103.2, and ΔH°_f298(MoO⁺) = 1103.5 kJ mol^-1. © 2015 American Chemical Society

Original language	English
Pages (from-to)	4643-4654
Journal	The Journal of Physical Chemistry A
Volume	120
Issue number	27
Online published	1 Oct 2015
DOIs	https://doi.org/10.1021/acs.jpca.5b07939
Publication status	Published - 14 Jul 2016

Access Output

10.1021/acs.jpca.5b07939

Other Access Options

Check CityUHK Library

Permanent Link

Right click to copy link

Cite this

@article{313b3ac3f96448daa733e0ebe4415fa1,

title = "Rotationally Resolved State-to-State Photoelectron Study of Molybdenum Monoxide Cation (MoO+)",

abstract = "By employing the two-color visible-ultraviolet (vis-UV) laser pulsed field ionization-photoelectron (PFI-PE) measurement, we have obtained rotationally selected and resolved photoelectron spectra for the MoO+(X4∑- v+ = 0, 1, and 2) and MoO+(a2Δ3/2,5/2; v+ = 0 and 1) cationic states. The unambiguous rotational assignments have made possible the determination of highly precise values for the band origin v00+ = 60 147.9 ± 0.8 cm-1, rotation constant B0+ = 0.4546 ± 0.0006 cm-1, spin-spin coupling constant λ = 26.454 ± 0.017 cm-1, and bond length re+ = 1.642 ± 0.001 {\AA} for the MoO+(X4∑-) ground state; v00+ = 60 556.4 ± 0.8 cm-1, B0+ = 0.4711 ± 0.0005 cm-1, and r0+ = 1.613 ± 0.001 {\AA} for the MoO+ (a2Δ3/2) excited state; and v00+ = 61 718.2 ± 0.8 cm-1, B0+ = 0.4695 ± 0.0006 cm-1, and r0+ = 1.616 ± 0.001 {\AA} for the MoO+ (a2Δ5/2) excited state. The ionization energy (IE) for MoO is determined to be IE(MoO) = 60 095.1 ± 0.8 cm-1 [7.4508 ± 0.0001 eV]. Furthermore, the vibrational constants are determined as ωe+ = 1000 ± 9 cm-1 and ωe+xe+ = 5 ± 3 cm-1 for MoO+(X4∑-); the vibration spacing ΔG(1/2) for MoO+(a2Δ3/2) is also measured as 1065 ± 4 cm-1. On the basis of the thermochemical cycle, together with the known IE(Mo) and the IE(MoO) determined in this study, the difference of 0 K bond dissociation energy for MoO+ and that for MoO is determined to be D0(Mo+-O) - D0(Mo-O) = IE(Mo) - IE(MoO) = -2890.8 ± 0.9 cm-1 [-0.3584 ± 0.0001 eV]. The energetic and spectroscopic values determined here have been used for benchmarking calculations at the CCSDTQ/CBS level of theory. The CCSDTQ/CBS predictions, IE(MoO) = 7.457 eV, re+ = 1.651 {\AA}, ωe+ = 974 cm-1, D0(Mo-O) = 5.386, and D0(Mo+-O) = 5.015 eV, are found to be in good agreement with the vis-UV PFI-PE measurements. We also recommend a set of equally reliable CCSDTQ/CBS thermochemical values for MoO and MoO+: ΔH°f0(MoO) = 383.7, ΔH°f298(MoO) = 384.0, ΔH°f0(MoO+) = 1103.2, and ΔH°f298(MoO+) = 1103.5 kJ mol-1. {\textcopyright} 2015 American Chemical Society",

author = "Zhihong Luo and Yih-Chung Chang and Yi Pan and Kai-Chung Lau and Ng, {C. Y.}",

year = "2016",

month = jul,

day = "14",

doi = "10.1021/acs.jpca.5b07939",

language = "English",

volume = "120",

pages = "4643--4654",

journal = "The Journal of Physical Chemistry A",

issn = "1089-5639",

publisher = "American Chemical Society",

number = "27",

}

TY - JOUR

T1 - Rotationally Resolved State-to-State Photoelectron Study of Molybdenum Monoxide Cation (MoO+)

AU - Luo, Zhihong

AU - Chang, Yih-Chung

AU - Pan, Yi

AU - Lau, Kai-Chung

AU - Ng, C. Y.

PY - 2016/7/14

Y1 - 2016/7/14

N2 - By employing the two-color visible-ultraviolet (vis-UV) laser pulsed field ionization-photoelectron (PFI-PE) measurement, we have obtained rotationally selected and resolved photoelectron spectra for the MoO+(X4∑- v+ = 0, 1, and 2) and MoO+(a2Δ3/2,5/2; v+ = 0 and 1) cationic states. The unambiguous rotational assignments have made possible the determination of highly precise values for the band origin v00+ = 60 147.9 ± 0.8 cm-1, rotation constant B0+ = 0.4546 ± 0.0006 cm-1, spin-spin coupling constant λ = 26.454 ± 0.017 cm-1, and bond length re+ = 1.642 ± 0.001 Å for the MoO+(X4∑-) ground state; v00+ = 60 556.4 ± 0.8 cm-1, B0+ = 0.4711 ± 0.0005 cm-1, and r0+ = 1.613 ± 0.001 Å for the MoO+ (a2Δ3/2) excited state; and v00+ = 61 718.2 ± 0.8 cm-1, B0+ = 0.4695 ± 0.0006 cm-1, and r0+ = 1.616 ± 0.001 Å for the MoO+ (a2Δ5/2) excited state. The ionization energy (IE) for MoO is determined to be IE(MoO) = 60 095.1 ± 0.8 cm-1 [7.4508 ± 0.0001 eV]. Furthermore, the vibrational constants are determined as ωe+ = 1000 ± 9 cm-1 and ωe+xe+ = 5 ± 3 cm-1 for MoO+(X4∑-); the vibration spacing ΔG(1/2) for MoO+(a2Δ3/2) is also measured as 1065 ± 4 cm-1. On the basis of the thermochemical cycle, together with the known IE(Mo) and the IE(MoO) determined in this study, the difference of 0 K bond dissociation energy for MoO+ and that for MoO is determined to be D0(Mo+-O) - D0(Mo-O) = IE(Mo) - IE(MoO) = -2890.8 ± 0.9 cm-1 [-0.3584 ± 0.0001 eV]. The energetic and spectroscopic values determined here have been used for benchmarking calculations at the CCSDTQ/CBS level of theory. The CCSDTQ/CBS predictions, IE(MoO) = 7.457 eV, re+ = 1.651 Å, ωe+ = 974 cm-1, D0(Mo-O) = 5.386, and D0(Mo+-O) = 5.015 eV, are found to be in good agreement with the vis-UV PFI-PE measurements. We also recommend a set of equally reliable CCSDTQ/CBS thermochemical values for MoO and MoO+: ΔH°f0(MoO) = 383.7, ΔH°f298(MoO) = 384.0, ΔH°f0(MoO+) = 1103.2, and ΔH°f298(MoO+) = 1103.5 kJ mol-1. © 2015 American Chemical Society

AB - By employing the two-color visible-ultraviolet (vis-UV) laser pulsed field ionization-photoelectron (PFI-PE) measurement, we have obtained rotationally selected and resolved photoelectron spectra for the MoO+(X4∑- v+ = 0, 1, and 2) and MoO+(a2Δ3/2,5/2; v+ = 0 and 1) cationic states. The unambiguous rotational assignments have made possible the determination of highly precise values for the band origin v00+ = 60 147.9 ± 0.8 cm-1, rotation constant B0+ = 0.4546 ± 0.0006 cm-1, spin-spin coupling constant λ = 26.454 ± 0.017 cm-1, and bond length re+ = 1.642 ± 0.001 Å for the MoO+(X4∑-) ground state; v00+ = 60 556.4 ± 0.8 cm-1, B0+ = 0.4711 ± 0.0005 cm-1, and r0+ = 1.613 ± 0.001 Å for the MoO+ (a2Δ3/2) excited state; and v00+ = 61 718.2 ± 0.8 cm-1, B0+ = 0.4695 ± 0.0006 cm-1, and r0+ = 1.616 ± 0.001 Å for the MoO+ (a2Δ5/2) excited state. The ionization energy (IE) for MoO is determined to be IE(MoO) = 60 095.1 ± 0.8 cm-1 [7.4508 ± 0.0001 eV]. Furthermore, the vibrational constants are determined as ωe+ = 1000 ± 9 cm-1 and ωe+xe+ = 5 ± 3 cm-1 for MoO+(X4∑-); the vibration spacing ΔG(1/2) for MoO+(a2Δ3/2) is also measured as 1065 ± 4 cm-1. On the basis of the thermochemical cycle, together with the known IE(Mo) and the IE(MoO) determined in this study, the difference of 0 K bond dissociation energy for MoO+ and that for MoO is determined to be D0(Mo+-O) - D0(Mo-O) = IE(Mo) - IE(MoO) = -2890.8 ± 0.9 cm-1 [-0.3584 ± 0.0001 eV]. The energetic and spectroscopic values determined here have been used for benchmarking calculations at the CCSDTQ/CBS level of theory. The CCSDTQ/CBS predictions, IE(MoO) = 7.457 eV, re+ = 1.651 Å, ωe+ = 974 cm-1, D0(Mo-O) = 5.386, and D0(Mo+-O) = 5.015 eV, are found to be in good agreement with the vis-UV PFI-PE measurements. We also recommend a set of equally reliable CCSDTQ/CBS thermochemical values for MoO and MoO+: ΔH°f0(MoO) = 383.7, ΔH°f298(MoO) = 384.0, ΔH°f0(MoO+) = 1103.2, and ΔH°f298(MoO+) = 1103.5 kJ mol-1. © 2015 American Chemical Society

UR - http://www.scopus.com/inward/record.url?scp=84978731597&partnerID=8YFLogxK

UR - https://www.scopus.com/record/pubmetrics.uri?eid=2-s2.0-84978731597&origin=recordpage

U2 - 10.1021/acs.jpca.5b07939

DO - 10.1021/acs.jpca.5b07939

M3 - RGC 21 - Publication in refereed journal

SN - 1089-5639

VL - 120

SP - 4643

EP - 4654

JO - The Journal of Physical Chemistry A

JF - The Journal of Physical Chemistry A

IS - 27

ER -