Temperature-dependent standard volumetric properties of hexamethylenetetramine in ordinary and deuterated water: A study resolving debatable issues being commented in the [Journal of Molecular Liquids, 248 (2017) 48–52]

Ivanov, E. V.

doi:10.1016/j.molliq.2018.09.046

Cited by 9 publications

(2 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The (H 2 O) m and HMTA • mH 2 O complexes denote the corresponding water clathrate and the mixed aggregate between water and HMTA molecules, respectively, and both are constituted through hydrogen bonds [15][16][17][18]. Parameter m is the number of water molecules that are associated in the formation of the water clathrate and mixed aggregate.…”

Section: Structural Processes In Hmta Aqueous Solutionsmentioning

confidence: 99%

Identification of Aggregation Processes in Hexamethylenetetramine Aqueous Solutions: A Comprehensive Raman and Acoustic Spectroscopic Study Combined with Density Functional Theory Calculations

Tsigoias,

Papanikolaou,

Kabanos

et al. 2023

Molecules

View full text Add to dashboard Cite

Raman scattering has been employed to study in detail the concentration dependence of the vibrational modes for hexamethylenetetramine (HMTA) aqueous solutions. The formation of protonated and/or aggregated species has been clarified by comparing the experimental with the theoretically predicted vibrational spectra by means of quantum mechanical calculations. The analysis has shown that the vibrational modes of the solutions arise from a contribution of the vibrational modes of the HMTA self-aggregates and hetero-aggregates of HMTA with water molecules that are formed in the low- and intermediate-concentration regions, respectively. The protonation of HMTA is ruled out due to the large differences between the experimental and the theoretically calculated spectra of the protonated molecules of HTMA in the fingerprint region. In the low-concentration solutions, the hetero-aggregation reaction of HMTA with water is the dominant mechanism, while at higher concentrations, a self-aggregation mechanism occurs. Ultrasonic absorption and velocity measurements were carried out for hexamethylenetetramine aqueous solutions. The acoustic spectra reveal the presence of only one single Debye-type relaxation process that is assigned to the aggregation mechanism of HMTA. The sound absorption data follow two different dependencies on the HMTA mole fraction. The crossover 0.018 mole fraction signifies two separate regions with distinct structural characteristics. The relaxation mechanism observed in dilute solutions was attributed to hetero-association of HMTA with water molecules, while at higher concentrations, the observed relaxation process was assigned to the self-association reaction of HMTA molecules. This structural transformation is also reflected in several physicochemical properties of the system, including the kinematic viscosity, the mass density, the sound speed and the adiabatic compressibility of the HMTA aqueous solutions. The combination of vibrational and acoustic spectroscopies with molecular orbital calculations allowed us to disentangle the underlying processes and to elucidate the observed relaxation mechanism in the HMTA aqueous solutions.

show abstract

Section: Structural Processes In Hmta Aqueous Solutionsmentioning

confidence: 99%

Identification of Aggregation Processes in Hexamethylenetetramine Aqueous Solutions: A Comprehensive Raman and Acoustic Spectroscopic Study Combined with Density Functional Theory Calculations

Tsigoias,

Papanikolaou,

Kabanos

et al. 2023

Molecules

View full text Add to dashboard Cite

show abstract

“…The methods and theories for obtaining the standard thermodynamic properties of bulk fluids have been very well established. Taking the Henry's constant as an example (Kazarina et al, 2023), the infinitely dilute state is set as the reference and standard states, and the Henry's constant is obtained from the experimental data by taking the limit of zero composition (Ivanov, 2018) based on the law of colligative properties of solutions (Aghaie et al, 2019;Chen et al, 2021). Principally, such a method can be used to determine the thermodynamic properties of the interfacial fluids, for example, the ILs immobilized on the solid surface.…”

Section: Introductionmentioning

confidence: 99%

Determination of standard molar volume of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide on titanium dioxide surface

Ye,

Dai,

Chen

et al. 2024

Front. Chem.

View full text Add to dashboard Cite

The fluids near the solid substrate display different properties compared to the bulk fluids owing to the asymmetric interaction between the fluid and substrate; however, to the best of our knowledge, no work has been conducted to determine the interfacial properties of fluids experimentally. In this work, we combined a pycnometer with experimental measurements and data processing to determine the standard thermodynamic properties of interfacial fluids for the first time. In the study, 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Hmim][NTf2]) and titanium dioxide (P25) were chosen as the probes to prove the concept. It was found that, with the combination of the Gay-Lussac pycnometer and the colligative law, together with selecting a suitable solvent, it is possible and reliable to determine the standard molar volume of the immobilized [Hmim][NTf2]. Compared to the bulk phase, the molar volumes of [Hmim][NTf2] on the P25 surface reduce by 20.8%–23.7% at temperatures from 293.15 to 323.15 K, and the reduction degrees decrease with increasing temperatures. The newly determined standard thermodynamic data was used to obtain the model parameters of hybrid electrolyte perturbed-chain statistical associating fluid theory density functional theory (ePC-SAFT-DFT), and further predictions of the density of interfacial ionic liquids with different film thicknesses were proved to be reliable in comparison with the experiment results.

show abstract

Volume properties of tetramethylenediethylenetetramine (pharmaceutical teotropine) in aqueous solutions between 278.15 and 318.15 K

Ivanov

Lebedeva

Baranov

et al. 2022

The Journal of Chemical Thermodynamics

View full text Add to dashboard Cite

Temperature-dependent standard volumetric properties of hexamethylenetetramine in ordinary and deuterated water: A study resolving debatable issues being commented in the [Journal of Molecular Liquids, 248 (2017) 48–52]

Cited by 9 publications

References 39 publications

Identification of Aggregation Processes in Hexamethylenetetramine Aqueous Solutions: A Comprehensive Raman and Acoustic Spectroscopic Study Combined with Density Functional Theory Calculations

Identification of Aggregation Processes in Hexamethylenetetramine Aqueous Solutions: A Comprehensive Raman and Acoustic Spectroscopic Study Combined with Density Functional Theory Calculations

Determination of standard molar volume of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide on titanium dioxide surface

Volume properties of tetramethylenediethylenetetramine (pharmaceutical teotropine) in aqueous solutions between 278.15 and 318.15 K

Contact Info

Product

Resources

About