Lithuanian Journal of Physics

Title

Tue, 28 Apr 2026 00:00:00 +0300

Introduction

Tue, 28 Apr 2026 00:00:00 +0300

The presence of Professor Vytautas Balevičius at the premises of the Institute of Chemical Physics in Saulėtekis is unmistakable. His loud, joyful conversations with colleagues in the corridor and his distinctive laugh are immediately recognizable. Although naturally talkative, what truly distinguishes him is his enduring, almost childlike passion for physics and his remarkable willingness to share knowledge. His office door has always been open to colleagues and students alike: one could knock to discuss a scientific problem and typically leave – if not with a definitive answer – then at least with a valuable reference or an insightful suggestion pointing toward the right direction. He is equally appreciated by students. Although Vytautas Balevičius stopped delivering regular lectures only a few years ago, those fortunate enough to attend his classes vividly recall his unconventional teaching style, lucid explanations, well-chosen examples, and the characteristic panache with which he presented the material.

Professor Vytautas Balevičius will celebrate his 75th birthday on 26 July 2026. This milestone is difficult to infer either from his youthful appearance – which suggests a considerably smaller number – or from his current level of activity. He continues to chop wood and clean the chimney of his house himself, and he still remains scientifically active at the Institute of Chemical Physics as Professor Emeritus. His career as a professional physicist began in 1969 when he enrolled in the Faculty of Physics at Vilnius University. He joined the Radiospectroscopy Group at the Department of General Physics and Spectroscopy during his sophomore year. Under the supervision of Professor Liudvikas Kimtys, he performed his first serious NMR measurements on organic mixtures exhibiting hydrogen bonding. His early scientific results were presented at several student conferences, culminating in the award of a medal from the then Ministry of Higher and Specialized Secondary Education for the best student work in 1973.

After graduating from the Faculty of Physics in 1974, V. Balevičius remained with the Radiospectroscopy Group as an assistant. He continued his investigations into the properties of organic mixtures and hydrogen bonding using NMR spectroscopy. Although he never enrolled in a PhD program, V. Balevičius managed to prepare his Doctoral Dissertation entitled ‘NMR spectroscopy of ternary systems with hydrogen bonding’. The dissertation was mainly based on five publications [1–5], two of which appeared – notably for that time – in the journal published beyond the Iron Curtain, Organic Magnetic Resonance. He successfully defended his dissertation at the Institute of Physics of the Academy

of Sciences of the Belorussian SSR in Minsk in 1977, receiving the degree of Candidate of Sciences in Physics and Mathematics. The reviewers of his dissertation were Prof. P. M. Borodin (St. Petersburg University) and N. N. Shapetko (Karpov Institute, Moscow).

Professor Balevičius has cultivated extensive and long-standing international collaborations. In 1979–1980, he worked as a postdoctoral researcher at the National Institute of Chemistry in Ljubljana, Slovenia. Under the supervision of Professor Dušan Hadži (1921–2019), one of the pioneers of hydrogen-bond research, he investigated phase transitions in organic systems using vibrational spectroscopy. During this period, he initiated fruitful collaborations with prominent Slovenian scientists Jernej Stare, Janez Mavri, Janez Plavec and Professor Robert Blinc (1933–2011). More than two decades later, in 2002, he returned to Slovenia for another extended research stay devoted primarily to studying hydrogen-bonded molecular systems.

Between 1990 and 1992, V. Balevičius conducted research at the Darmstadt University of Technology, Germany, as a recipient of an Alexander von Humboldt Fellowship. Working with Professor Alarich Weiss and Professor Dieter Woermann (University of Cologne), he redirected part of his scientific focus toward NMR studies of phase transitions in complex ternary aqueous systems of organic compounds and inorganic salts. He was among the first to apply novel time renormalization group approaches and decorated lattice models to interpret the dependence of phase diagrams of such complex molecular systems on salt type and concentration. During his stay in Darmstadt, he also established a collaboration with Professor Hartmut Fuess, studying critical phenomena in binary salt solutions using NMR relaxation measurements. V. Balevičius later coordinated several bilateral German-Lithuanian research projects on phase transitions in ionic systems and dynamic nuclear polarization in solid-state materials.

The scientific achievements of V. Balevičius during 1974–1995 were summarized in his Habilitation Thesis entitled ‘NMR and vibrational spectroscopy of phase transitions in partially ordered systems’. This work presented original contributions to the understanding of phase transitions in liquids and orientationally disordered crystals, as well as order-disorder phenomena in organic and ionic solutions studied by NMR, IR absorption and Raman spectroscopy. He successfully defended his habilitation at Vilnius University in 1996 and was awarded the degree of Doctor habilitatus.

In the post-habilitation period, Professor Balevičius expanded his research toward NMR investigations of ionic liquids, lyotropic chromonic liquid crystals of biomedical relevance, solid-state polymers, and low-dimensional proton conductors with potential applications in innovative medicine. In these areas, he collaborated extensively with Prof. Zofia Gdaniec (Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznań), Prof. Vladimir I. Chizhik (St. Petersburg University), Professors Valeriy Pogorelov and Iryna Doroshenko (Taras Shevchenko National University of Kyiv), Dr. Vaidas Klimkevičius (Vilnius University), Prof. Aivaras Kareiva (Vilnius University), Prof. Jūras Banys (Vilnius University) and Prof. Jérôme Hirschinger (Strasbourg University). In addition, proton stretching with anharmonic coupling in strongly hydrogen-bonded molecular systems was investigated by IR spectroscopy in close collaboration with Dr. George Pitsevich (Belarusian State University, Minsk).

Over the course of his career, V. Balevičius has authored more than 130 scientific publications and delivered over 100 invited and contributed presentations at international conferences. In 2012, he shared the Lithuanian Science Prize of the Lithuanian Academy of Sciences with his close colleague Prof. Valdas Šablinskas – the highest national recognition for scientific achievements. In 2016, the International Association of Advanced Materials honoured him with its medal in recognition of his significant contributions to materials science, engineering and technology.

Professor V. Balevičius has earned the trust of the Faculty of Physics community, serving as Head of the Department of General Physics and Spectroscopy (2006–2015) and as Dean of the Faculty (2007–2017). He has played a pivotal role in establishing modern NMR and EPR laboratories at the Faculty of Physics of Vilnius University in 2012. He also secured support from the Alexander von Humboldt Foundation for the acquisition of advanced vibrational spectroscopy equipment, including a high-power continuous-wave argon laser and a Bruker FTIR Vertex spectrometer. He has supervised three PhD students Valdas Šablinskas, Vytautas Klimavičius and Laurynas Dagys, and he served as consultant to a PhD student Kristina Kristinaitytė. Valdas Šablinskas became a leading specialist in vibrational spectroscopy at Vilnius University and later headed both the Department of General Physics and Spectroscopy and the newly established Institute of Chemical Physics at the Faculty of Physics. Vytautas Klimavičius defended his PhD Thesis in 2017 and subsequently received an Alexander von Humboldt Fellowship to pursue advanced studies of dynamic nuclear polarization in solid-state materials at the Darmstadt University of Technology. He returned to Vilnius University in 2020, and now leads the NMR Laboratory at the Institute of Chemical Physics. Laurynas Dagys obtained his PhD in 2019. He completed postdoctoral work in the NMR group of Professor Malcolm Levitt at the University of Southampton where he investigated spin dynamics in high and low magnetic fields during the period 2018–2022. Together with colleagues, L. Dagys received the prestigious Schrödinger Award in 2021. After a period at

NVision Imaging Technologies GmbH in Ulm, he returned to the Institute of Chemical Physics in 2023 and contributes to the advancement of NMR research at the Institute.

This special issue of the Lithuanian Journal of Physics is a tribute from colleagues and friends of Vytautas

Balevičius on the occasion of his 75th birthday. It is offered in sincere appreciation of his many years of fruitful collaboration, inspiring scientific discussions, dedicated mentorship, and enduring friendship.

Prof. Dr. Habil. Liudvikas Kimtys† and Prof. Dr. Kęstutis Aidas

27 February 2026

References

[1]L. Kimtys, V. Balevičius, and M.L. Balevičius, The correlation of chemical shifts of hydroxyl protons and hydroxyl hydrogen charges, Liet. Fiz. Rink. 15, 398 (1975).

[2]V. Balevičius and L. Kimtys, Temperature dependences of 1H NMR shift of trimethylacetic acid in DMSO, Liet. Fiz. Rink. 15, 1041 (1975).

[3]V. Balevičius and L. Kimtys, Analysis of association processes of trimethylacetic acid in acetone: the quasi-lattice approximation, Liet. Fiz. Rink. 16, 685 (1976).

[4]V. Balevičius and L. Kimtys, A 1H NMR study of hydrogen bonding and complexation processes of trimethylacetic acid in acetone, Org. Magn. Reson. 8, 180 (1976).

[5]V. Balevičius and L. Kimtys, An 1H n.m.r. study of complexation and self-association processes in the ternary system: tert-butyl alcohol–acetone–cyclohexane, Org. Magn. Reson. 9, 489 (1977).

Conformational analysis of small ethanol clusters trapped in a low-temperature argon matrix

Iryna Doroshenko, Askar Nekboev, Bahrom Kuyliev — Tue, 28 Apr 2026 00:00:00 +0300

This work presents a conformational analysis of ethanol molecules and their clusters isolated in a low-temperature argon matrix using FTIR spectroscopy and quantum-chemical calculations. Optimal geometry, energy parameters and vibrational frequencies for trans and gauche conformations of ethanol, as well as for various possible combinations of conformers in dimers, trimers and tetramers, were calculated. Temperature-dependent FTIR spectra reveal distinct bands corresponding to the O–H stretching vibrations of both conformers. As the matrix temperature increases from 20 to 50 K, ethanol monomers progressively form hydrogen-bonded clusters. Quantum-chemical modelling confirms the presence of all theoretically predicted cluster configurations in the matrix at temperatures about 40 K.

Thermophilic proteins – exploring thermal stability of FN3 domain from Thermoanaerobacter tengcongensis based on in silico experiments

Chaitali Barman, Aneta Jezierska, Jarosław J. Panek — Tue, 28 Apr 2026 00:00:00 +0300

Extremophilic proteins exhibit a remarkable stability under extreme conditions (e.g. thermophilic systems are stable at elevated temperatures), offering insights into molecular adaptations and early life on Earth. Currently, thermophilic organisms are widely investigated, and they constitute a challenge for new industrial and pharmaceutical applications. Examples of studies on extremophiles, including thermophiles, reach as far as space exploration experiments. The Fibronectin Type 3 (FN3) domain, a conserved structural motif, plays key roles in protein interactions and stability. This study investigates the thermal stability of the FN3 domain from the thermophilic bacterium Thermoanaerobacter tengcongensis. The domains of the wild type and its triple mutant FN3 were simulated (Protein Data Bank ids: 7jgt and 7jgu, respectively), with a wild-type human analogue (Protein Data Bank id: 5kf4) as a control, using molecular dynamics (MD) with classical force field. The simulations were performed at 300, 350 and 400 K temperatures to show their impact on the molecular properties. Structural parameters were analyzed, including root mean square deviation (RMSD), root mean square fluctuations (RMSF), solvent accessible surface area (SASA), secondary structure assignment and hydrogen bond networks. The obtained results reveal that the thermophilic bacterial variants of the FN3 domain exhibit lower structural fluctuations, particularly in residues 10–20 and 50–60, compared to the human analogue. The bacterial FN3 mutant exhibited reduced stability compared to the wild type, highlighting the importance of hydrogen bonding network in ensuring thermal stability. These findings enhance our understanding of the molecular mechanisms underlying the stability and adaptation of extremophilic proteins to high temperatures.

Could carotenoids advance the sensing properties of KL1421 luminophore? Theoretical study

Jelena Tamulienė, Teodora Kirova, Artis Kinens, Roman Viter — Tue, 28 Apr 2026 00:00:00 +0300

This computational chemistry research was performed using Becke’s three-parameter hybrid functional approach with the non-local correlation provided by Lee, Yang and Parr, and the cc-pVTZ basis set. The geometry, its change, and the charge redistribution in KL1421 when the molecule interacts with carotenoids and/or sensed molecules such as NH3 and acetic acid were studied. The orbital diagrams were used to illustrate the excitations and their variations resulting from the formation of the above complexes. The increase in molar absorptivity is observed in compounds with carotenoids, leading to a higher absorbance of KL1421. The latter allows us to conclude that a large amount of energy could be emitted, or the emission becomes longer. Additionally, the analysis of the oscillator strengths reveals that the strong interaction among species in KL1421 could facilitate radiation emission. We concluded that carotenoids could improve the sensing properties of the KL1421 luminophore.

Investigation of visceral adipose tissue (VAT) surface using microscopic methods

Edvardas Brimas, Inga Grigoravičiūtė, Aivaras Kareiva — Wed, 29 Apr 2026 15:15:36 +0300

In this study, optical microscopy (OM) and scanning electron microscopy (SEM) were used to characterize visceral adipose tissue (VAT) samples collected from volunteer patients with obesity. The focus was on examining the relationship between the morphological features of VAT samples from individuals with and without metabolic diseases. The microscopic images provided insights into the key morphological characteristics of VAT layers in obese individuals. The OM images of adipose tissue from visceral layers of various obese patients with metabolic diseases revealed the formation of lipid droplets of varying sizes and oval shapes. The SEM micrographs of VAT samples from obese patients with metabolic diseases showed the presence of single circular formations, voids, and other distinct morphological features. The OM and SEM findings could potentially be used to assess metabolic symptoms and predict various diseases in patients with obesity.

Relaxation dynamics of guanosine 5’-monophosphate with Na+ and K+ in aqueous solutions investigated by broadband dielectric spectroscopy

Ilona Zamaraitė, Andrius Džiaugys, Jūras Banys — Tue, 28 Apr 2026 00:00:00 +0300

To gain insights into nucleotide–monovalent ions interaction, the dynamics of counterions (sodium and potassium) with guanosine 5'-monophosphate (5'-GMP) were studied in an aqueous solution via broadband dielectric spectroscopy measurements. Complex reflection coefficients of aqueous Na-GMP and K-GMP solutions are measured in the frequency domain at room temperature. Complex specific resistance spectra are analyzed at various mononucleotide concentrations. One dispersion region located at 100 MHz was observed. It is interpreted as being caused by DNA counterion fluctuations. It largely depends on the GMP concentration in the solution.

Experimental (Raman and IR) and computational (DFT) studies of the cyclohexyltrifluorosilane

Tue, 28 Apr 2026 00:00:00 +0300

This study presents an experimental (Raman and IR spectroscopy) and computational (DFT) investigation of cyclohexyltrifluorosilane to identify its stable conformers and assign its experimental vibrational spectral bands. Computational analysis confirmed the existence of two stable chair conformers: chair equatorial (most stable) and chair axial. The potential energy difference between these conformers was found to be 6.3 kJ/mol, and the interconversion barrier was determined to be too high to overcome it at matrix experiments conditions. To provide a complete assignment of the compound’s vibrational spectral bands, experimental data from ATR-FTIR, Raman, and matrix isolation IR spectroscopy were used in conjunction with DFT calculations. The experimental results confirm the existence of only one conformer in the chair equatorial configuration.

On the proton spin diffusion in powdered fumaric acid

Laurynas Dagys — Tue, 28 Apr 2026 00:00:00 +0300

Spin diffusion is a well-established phenomenon in solid-state NMR, providing means to probe the molecular structure and transfer magnetization over extended intramolecular distances. Recently, we demonstrated that highly polarized 13C nuclei in 1-13C-fumaric acid can relay magnetization across crystallite boundaries to other 13C-labelled powders. To explore the possibility of using the abundant 1H network, in the present study, dry powdered fumaric acid was examined using conventional solid-state NMR techniques characterizing local order, relaxation and dynamical properties. The results reveal that, although 1H spin diffusion is intrinsically slow, both the diffusion rate and polarization lifetime increase with temperature. This offers new practical insights into the proton-mediated spin diffusion and may aid in designing more eﬀicient polarization-relay strategies.

Lithuanian Journal of Physics

Title

Contents

Introduction

Conformational analysis of small ethanol clusters trapped in a low-temperature argon matrix

Thermophilic proteins – exploring thermal stability of FN3 domain from Thermoanaerobacter tengcongensis based on in silico experiments

Could carotenoids advance the sensing properties of KL1421 luminophore? Theoretical study

Investigation of visceral adipose tissue (VAT) surface using microscopic methods

Relaxation dynamics of guanosine 5’-monophosphate with Na+ and K+ in aqueous solutions investigated by broadband dielectric spectroscopy

Experimental (Raman and IR) and computational (DFT) studies of the cyclohexyltrifluorosilane

On the proton spin diffusion in powdered fumaric acid