The Experts below are selected from a list of 216 Experts worldwide ranked by ideXlab platform
Joseph S Francisco - One of the best experts on this subject based on the ideXlab platform.
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relative vibrational overtone intensity of cis cis and trans perp peroxynitrous acid
Journal of Chemical Physics, 2004Co-Authors: Jamie Matthews, Amitabha Sinha, Joseph S FranciscoAbstract:The vibrational overtone spectrum of HOONO is examined in the region of the 2νOH and 3νOH bands using action spectroscopy in conjunction with ab initio intensity calculations. The present measurements indicate that the oscillator strength associated with the higher energy trans–perp conformer of HOONO is stronger relative to the lower energy cis–cis conformer for both these vibrational overtone levels. Ab initio intensity calculations carried out at the QCISD level of theory suggest that this disparity in oscillator strength apparently arises from differences in the second derivative of the transition dipole Moment Function of the two isomers. The calculations indicate that the oscillator strength for the trans–perp isomer is ∼5.4 times larger than that of the cis–cis isomer for the 2νOH band and ∼2 times larger for 3νOH band. The band positions and intensities predicted by the calculations are used to aid in the assignment of features in the experimental action spectra associated with the OH stretching o...
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Relative vibrational overtone intensity of cis–cis and trans–perp peroxynitrous acid
Journal of Chemical Physics, 2004Co-Authors: Jamie Matthews, Amitabha Sinha, Joseph S FranciscoAbstract:The vibrational overtone spectrum of HOONO is examined in the region of the 2νOH and 3νOH bands using action spectroscopy in conjunction with ab initio intensity calculations. The present measurements indicate that the oscillator strength associated with the higher energy trans–perp conformer of HOONO is stronger relative to the lower energy cis–cis conformer for both these vibrational overtone levels. Ab initio intensity calculations carried out at the QCISD level of theory suggest that this disparity in oscillator strength apparently arises from differences in the second derivative of the transition dipole Moment Function of the two isomers. The calculations indicate that the oscillator strength for the trans–perp isomer is ∼5.4 times larger than that of the cis–cis isomer for the 2νOH band and ∼2 times larger for 3νOH band. The band positions and intensities predicted by the calculations are used to aid in the assignment of features in the experimental action spectra associated with the OH stretching o...
Jamie Matthews - One of the best experts on this subject based on the ideXlab platform.
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the oh stretching and ooh bending overtone spectrum of hoono
Journal of Chemical Physics, 2005Co-Authors: Daniel P Schofield, Jamie Matthews, Henrik G Kjaergaard, Amitabha SinhaAbstract:We have simulated the HOONO vibrational overtone spectrum with use of a local mode Hamiltonian that includes the OH-stretching, OOH-bending, and NOOH-torsional modes and coupling between all three modes. The local mode parameters and the dipole Moment Function are calculated with coupled-cluster ab initio theory and an augmented Dunning-type triple-zeta basis set. We investigate the accuracy of the local mode parameters obtained from two different potential-energy fitting routines, as well as the sensitivity of these parameters to the basis set employed. We compare our simulated spectra to previously published action spectra in the first and second OH-stretching overtone regions. In addition we have recorded the spectrum in the OH-stretch and OOH-bend combination region around 7700cm−1 and we also compare to this. Our simulated spectrum is in qualitative agreement with experiment in the first and second OH-stretching overtone and in the stretch-bend regions.
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relative vibrational overtone intensity of cis cis and trans perp peroxynitrous acid
Journal of Chemical Physics, 2004Co-Authors: Jamie Matthews, Amitabha Sinha, Joseph S FranciscoAbstract:The vibrational overtone spectrum of HOONO is examined in the region of the 2νOH and 3νOH bands using action spectroscopy in conjunction with ab initio intensity calculations. The present measurements indicate that the oscillator strength associated with the higher energy trans–perp conformer of HOONO is stronger relative to the lower energy cis–cis conformer for both these vibrational overtone levels. Ab initio intensity calculations carried out at the QCISD level of theory suggest that this disparity in oscillator strength apparently arises from differences in the second derivative of the transition dipole Moment Function of the two isomers. The calculations indicate that the oscillator strength for the trans–perp isomer is ∼5.4 times larger than that of the cis–cis isomer for the 2νOH band and ∼2 times larger for 3νOH band. The band positions and intensities predicted by the calculations are used to aid in the assignment of features in the experimental action spectra associated with the OH stretching o...
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Relative vibrational overtone intensity of cis–cis and trans–perp peroxynitrous acid
Journal of Chemical Physics, 2004Co-Authors: Jamie Matthews, Amitabha Sinha, Joseph S FranciscoAbstract:The vibrational overtone spectrum of HOONO is examined in the region of the 2νOH and 3νOH bands using action spectroscopy in conjunction with ab initio intensity calculations. The present measurements indicate that the oscillator strength associated with the higher energy trans–perp conformer of HOONO is stronger relative to the lower energy cis–cis conformer for both these vibrational overtone levels. Ab initio intensity calculations carried out at the QCISD level of theory suggest that this disparity in oscillator strength apparently arises from differences in the second derivative of the transition dipole Moment Function of the two isomers. The calculations indicate that the oscillator strength for the trans–perp isomer is ∼5.4 times larger than that of the cis–cis isomer for the 2νOH band and ∼2 times larger for 3νOH band. The band positions and intensities predicted by the calculations are used to aid in the assignment of features in the experimental action spectra associated with the OH stretching o...
Jianzhong Lin - One of the best experts on this subject based on the ideXlab platform.
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hybrid method of Moments with interpolation closure taylor series expansion method of Moments scheme for solving the smoluchowski coagulation equation
Applied Mathematical Modelling, 2017Co-Authors: Jianzhong LinAbstract:Abstract This paper presents a hybrid method of Moments with interpolation closure–Taylor-series expansion method of Moments (MoMIC–TEMoM) scheme for solving the Smoluchowski coagulation equation. In the proposed scheme, the exponential Function, which arises in the conversion from a particle size distribution space to a space of Moments, is expressed in an additive form using the third-order Taylor-series expansion; the implicit Moments are approximated using two Lagrange interpolation Functions, namely the newly defined normalized Moment Function and the normalized Moment Function defined by Frenklach and Harris (1987). The new hybrid scheme allows implementation of the method of Moments with an arbitrary type of Moment sequence, and it overcomes the shortcomings of the Taylor-series expansion Moment method proposed by Frenklach and Harris. The proposed scheme is verified with three aerosol dynamics, namely Brownian coagulation in the free molecular regime, Brownian coagulation in the continuum-slip regime, and turbulence coagulation. The results reveal that the hybrid MoMIC–TEMoM scheme has similar accuracy to currently recognized methods including the quadrature method of Moments, MoMIC, and TEMoM, and its accuracy can be further enhanced as the fractional Moment sequence type is used for Brownian coagulation in the free molecular regime. Thus, the proposed scheme is a reliable for solving the Smoluchowski coagulation equation.
Mingzhou Yu - One of the best experts on this subject based on the ideXlab platform.
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Hybrid method of Moments with interpolation closure–Taylor-series expansion method of Moments scheme for solving the Smoluchowski coagulation equation
Applied Mathematical Modelling, 2017Co-Authors: Mingzhou YuAbstract:Abstract This paper presents a hybrid method of Moments with interpolation closure–Taylor-series expansion method of Moments (MoMIC–TEMoM) scheme for solving the Smoluchowski coagulation equation. In the proposed scheme, the exponential Function, which arises in the conversion from a particle size distribution space to a space of Moments, is expressed in an additive form using the third-order Taylor-series expansion; the implicit Moments are approximated using two Lagrange interpolation Functions, namely the newly defined normalized Moment Function and the normalized Moment Function defined by Frenklach and Harris (1987). The new hybrid scheme allows implementation of the method of Moments with an arbitrary type of Moment sequence, and it overcomes the shortcomings of the Taylor-series expansion Moment method proposed by Frenklach and Harris. The proposed scheme is verified with three aerosol dynamics, namely Brownian coagulation in the free molecular regime, Brownian coagulation in the continuum-slip regime, and turbulence coagulation. The results reveal that the hybrid MoMIC–TEMoM scheme has similar accuracy to currently recognized methods including the quadrature method of Moments, MoMIC, and TEMoM, and its accuracy can be further enhanced as the fractional Moment sequence type is used for Brownian coagulation in the free molecular regime. Thus, the proposed scheme is a reliable for solving the Smoluchowski coagulation equation.
Amitabha Sinha - One of the best experts on this subject based on the ideXlab platform.
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the oh stretching and ooh bending overtone spectrum of hoono
Journal of Chemical Physics, 2005Co-Authors: Daniel P Schofield, Jamie Matthews, Henrik G Kjaergaard, Amitabha SinhaAbstract:We have simulated the HOONO vibrational overtone spectrum with use of a local mode Hamiltonian that includes the OH-stretching, OOH-bending, and NOOH-torsional modes and coupling between all three modes. The local mode parameters and the dipole Moment Function are calculated with coupled-cluster ab initio theory and an augmented Dunning-type triple-zeta basis set. We investigate the accuracy of the local mode parameters obtained from two different potential-energy fitting routines, as well as the sensitivity of these parameters to the basis set employed. We compare our simulated spectra to previously published action spectra in the first and second OH-stretching overtone regions. In addition we have recorded the spectrum in the OH-stretch and OOH-bend combination region around 7700cm−1 and we also compare to this. Our simulated spectrum is in qualitative agreement with experiment in the first and second OH-stretching overtone and in the stretch-bend regions.
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relative vibrational overtone intensity of cis cis and trans perp peroxynitrous acid
Journal of Chemical Physics, 2004Co-Authors: Jamie Matthews, Amitabha Sinha, Joseph S FranciscoAbstract:The vibrational overtone spectrum of HOONO is examined in the region of the 2νOH and 3νOH bands using action spectroscopy in conjunction with ab initio intensity calculations. The present measurements indicate that the oscillator strength associated with the higher energy trans–perp conformer of HOONO is stronger relative to the lower energy cis–cis conformer for both these vibrational overtone levels. Ab initio intensity calculations carried out at the QCISD level of theory suggest that this disparity in oscillator strength apparently arises from differences in the second derivative of the transition dipole Moment Function of the two isomers. The calculations indicate that the oscillator strength for the trans–perp isomer is ∼5.4 times larger than that of the cis–cis isomer for the 2νOH band and ∼2 times larger for 3νOH band. The band positions and intensities predicted by the calculations are used to aid in the assignment of features in the experimental action spectra associated with the OH stretching o...
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Relative vibrational overtone intensity of cis–cis and trans–perp peroxynitrous acid
Journal of Chemical Physics, 2004Co-Authors: Jamie Matthews, Amitabha Sinha, Joseph S FranciscoAbstract:The vibrational overtone spectrum of HOONO is examined in the region of the 2νOH and 3νOH bands using action spectroscopy in conjunction with ab initio intensity calculations. The present measurements indicate that the oscillator strength associated with the higher energy trans–perp conformer of HOONO is stronger relative to the lower energy cis–cis conformer for both these vibrational overtone levels. Ab initio intensity calculations carried out at the QCISD level of theory suggest that this disparity in oscillator strength apparently arises from differences in the second derivative of the transition dipole Moment Function of the two isomers. The calculations indicate that the oscillator strength for the trans–perp isomer is ∼5.4 times larger than that of the cis–cis isomer for the 2νOH band and ∼2 times larger for 3νOH band. The band positions and intensities predicted by the calculations are used to aid in the assignment of features in the experimental action spectra associated with the OH stretching o...