Spectroscopic Identification of Hydrogen Bond Vibrations and Quasi-Isostructural Polymorphism in N-Salicylideneaniline

Łukasz Hetmańczyk; Eugene A Goremychkin; Janusz Waliszewski; Mikhail V Vener; Paweł Lipkowski; Peter M Tolstoy; Aleksander Filarowski

doi:10.3390/molecules26165043

Spectroscopic Identification of Hydrogen Bond Vibrations and Quasi-Isostructural Polymorphism in N-Salicylideneaniline

Molecules. 2021 Aug 20;26(16):5043. doi: 10.3390/molecules26165043.

Authors

Łukasz Hetmańczyk¹, Eugene A Goremychkin², Janusz Waliszewski³, Mikhail V Vener^{4

5}, Paweł Lipkowski⁶, Peter M Tolstoy⁷, Aleksander Filarowski^{2

8}

Affiliations

¹ Faculty of Chemistry, Jagiellonian University, 2 Gronostajowa Str., 30-387 Cracow, Poland.
² Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research 6 F. Joliot-Curie str., 141980 Dubna, Russia.
³ Faculty of Physics, University of Bialystok, 1L Ciolkowskiego str., 15-245 Bialystok, Poland.
⁴ Quantum Chemistry Department, Mendeleev University of Chemical Technology, Miusskaya Square 9, 125047 Moscow, Russia.
⁵ Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninskii Prosp. 31, 119991 Moscow, Russia.
⁶ Department of Physical and Quantum Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańnskiego 27, 50-370 Wrocław, Poland.
⁷ Institute of Chemistry, St. Petersburg State University, Universitetskij pr. 26, 198504 Saint Petersburg, Russia.
⁸ Faculty of Chemistry, University of Wrocław 14 F. Joliot-Curie str., 50-383 Wrocław, Poland.

Abstract

The ortho-hydroxy aryl Schiff base 2-[(E)-(phenylimino)methyl]phenol and its deutero-derivative have been studied by the inelastic incoherent neutron scattering (IINS), infrared (IR) and Raman experimental methods, as well as by Density Functional Theory (DFT) and Density-Functional Perturbation Theory (DFPT) simulations. The assignments of vibrational modes within the 3500-50 cm^-1 spectral region made it possible to state that the strong hydrogen bond in the studied compound can be classified as the so-called quasi-aromatic bond. The isotopic substitution supplemented by the results of DFT calculations allowed us to identify vibrational bands associated with all five major hydrogen bond vibrations. Quasi-isostructural polymorphism of 2-[(E)-(phenylimino)methyl]phenol (SA) and 2-[(E)-(phenyl-D₅-imino)methyl]phenol (SA-C₆D₅) has been studied by powder X-ray diffraction in the 20-320 K temperature range.

Keywords: Schiff bases; hydrogen bond; inelastic incoherent neutron scattering; isotopic effect.

Grants and funding

18-13-00050/Russian Science Foundation