Dozmorov Nikolay

PhD student

Master of Science in Physics

Research interests:

Modeling of femtosecond dynamics of intramolecular processes
Setup automation

Education

Novosibirsk State University

2017 - now

Postgraduate in Physics, Minor: Chemical-Biological Physics

Modeling of intramolecular femtosecond dynamics in the excited electronic states in systems of varying complexity: molecular iodine, Van der Waals complex of iodine with argon, and complex "rubidium-helium nanodroplet"

Novosibirsk State University

2015 - 2017

Master of Science in Physics, Minor: Physical-technical Informatics

Modeling of intramolecular dynamics in the excited electronic states of iodine molecule and complex "rubidium-helium nanodroplet"

Novosibirsk State University

2011 - 2015

Bachelor of Science in Physics, Minor: Physical-technical Informatics

Automation of measurement of spectral dependencies of the mass spectrum and velocity maps of photofragments

Publications

Singlet Oxygen ¹O₂ in Photocatalysis on TiO₂. Where Does It Come from?

The Journal of Physical Chemistry C

Features of the near-infrared phosphorescence of singlet oxygen ¹O₂ photosensitized by TiO₂ in solutions have been investigated. The short-lived phosphorescence of ¹O₂ with spectral maximum at approximately 1300 nm is observed to follow excitation by pulsed laser radiation at 355 nm of TiO₂ suspended in CCl₄ and water H₂O. The shorter lifetime and spectral shift of this phosphorescence, as compared with phosphorescence of ¹O₂ sensitized by phenalenone in these solvents, are attributed to the adsorbed state of emitting singlet oxygen. The observed laser pulse energy dependence indicates the two-photon and three-photon nature of this phosphorescence initiation in CCl₄ and H₂O, respectively. The formation of ¹O₂ in CCl₄ is assumed to be provided by the sequence of one-photon excitation of TiO₂, giving rise to superoxide anion O₂^– and one-photon photodetachment of electron from O₂^–. The photodetachment of electron from O₂^– in water H₂O is a two-photon process because of higher solvation energy of superoxide anion in water. The processes that govern the rise and decay of singlet oxygen phosphorescence sensitized by TiO₂ are discussed. The factors affecting the yield of singlet oxygen provided by electron photodetachment are also considered.

Reply to Comments on “Singlet Oxygen ¹O₂ in Photocatalysis on TiO₂. Where Does It Come from?”

The Journal of Physical Chemistry C

In the Comment the authors Y. Nosaka and A. Y. Nosaka present arguments against the mechanism of singlet oxygen production which was suggested in the earlier published paper (Demyanenko et al., J. Phys. Chem. C 2019, 123, 2175) to explain the experimental data for the Near IR (NIR)-luminescence observed to appear after laser excitation at 355 nm of TiO₂ suspension in air-saturated solvents CCl₄ and H₂O. The main arguments of the Comment are directed against Assignment of the NIR Emission and Electron Photodetachment Mechanism suggested by Demyanenko et al.. Particularly the Comment claims that the red shift (near 30 nm) and bandwidth (50-60 nm) of the NIR luminescence observed in paper by Demyanenko et al. are too large to be assigned to the luminescence of singlet oxygen ¹O₂. In the Reply it is shown that several arguments of the Comment are based on the incorrect statements. The current interpretation of the nature of the red shift and bandwidth of the luminescence of singlet oxygen governed by interaction with the environment is considered. It is shown that the characteristics of NIR luminescence (rather large red shift and bandwidth as compared with the literature data for the luminescence of ¹O₂ in solutions) observed in experiments by Demyanenko et al. are in a qualitative agreement with expected tendencies. All the arguments of the Comment are considered in detail and extended reply is given.

An Automated Apparatus for Measuring Spectral Dependences of the Mass Spectra and Velocity Map Images of Photofragments

Instruments and Experimental Techniques

REMPI detection of singlet oxygen ¹O₂ arising from UV‑photodissociation of van der Waals complex isoprene-oxygen C₅H₈‑O₂

Chemical Physics Letters

Quantum dynamics of Rb atoms desorbing off the surface of He nanodroplets

Physical Review A

Role of ion-pair states in the predissociation dynamics of Rydberg states of molecular iodine

Physical Chemistry Chemical Physics

Using femtosecond pump–probe ion imaging spectroscopy, we establish the key role of I⁺ + I⁻ ion-pair (IP) states in the predissociation dynamics of molecular iodine I₂ excited to Rydberg states. Two-photon excitation of Rydberg states lying above the lowest IP state dissociation threshold (1st tier) is found to be followed by direct parallel transitions into IP states of the 1st tier asymptotically correlating to a pair of I ions in their lowest states I⁺(³P₂) + I⁻(¹S₀), of the 2nd tier correlating to I⁺(³P₀) + I⁻(¹S₀), and of the 3rd tier correlating to I⁺(¹D₂) + I⁻(¹S₀). Predissociation via the 1st tier proceeds presumably with a delay of 1.6–1.7 ps which is close to the vibrational period in the 3rd tier state (3rd tier-mediated process). The 2nd tier IP state is concluded to be the main precursor for predissociation via lower lying Rydberg states proceeding with a characteristic time of 7–8 ps and giving rise to Rydberg atoms I(5s²5p⁴6s¹). The channel generating I(²P_3/2) + I(²P_1/2) atoms with total kinetic energy corresponding to one-photon excitation is found to proceed via a pump – dump mechanism with dramatic change of angular anisotropy of this channel as compared with earlier nanosecond experiments.

Dozmorov Nikolay

PhD student

Research interests:

Education

Novosibirsk State University

Novosibirsk State University

Novosibirsk State University

Publications

Singlet Oxygen 1O2 in Photocatalysis on TiO2. Where Does It Come from?

Reply to Comments on “Singlet Oxygen 1O2 in Photocatalysis on TiO2. Where Does It Come from?”

An Automated Apparatus for Measuring Spectral Dependences of the Mass Spectra and Velocity Map Images of Photofragments

REMPI detection of singlet oxygen 1O2 arising from UV‑photodissociation of van der Waals complex isoprene-oxygen C5H8‑O2

Quantum dynamics of Rb atoms desorbing off the surface of He nanodroplets

Role of ion-pair states in the predissociation dynamics of Rydberg states of molecular iodine

Singlet Oxygen ¹O₂ in Photocatalysis on TiO₂. Where Does It Come from?

Reply to Comments on “Singlet Oxygen ¹O₂ in Photocatalysis on TiO₂. Where Does It Come from?”

REMPI detection of singlet oxygen ¹O₂ arising from UV‑photodissociation of van der Waals complex isoprene-oxygen C₅H₈‑O₂