1
|
Falourd X, Lahaye M, Rondeau-Mouro C. Assessment of cellulose interactions with water by ssNMR: 1H->13C transfer kinetics revisited. Carbohydr Polym 2022; 298:120104. [DOI: 10.1016/j.carbpol.2022.120104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/23/2022] [Accepted: 09/08/2022] [Indexed: 11/24/2022]
|
2
|
Klimavicius V, Maršalka A, Kizalaite A, Zarkov A, Kareiva A, Aidas K, Hirschinger J, Balevicius V. Step-by-step from amorphous phosphate to nano-structured calcium hydroxyapatite: monitoring by solid-state 1H and 31P NMR and spin dynamics. Phys Chem Chem Phys 2022; 24:18952-18965. [PMID: 35916288 DOI: 10.1039/d2cp02108k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The solid-state 1H, 31P NMR spectra and cross-polarization (CP MAS) kinetics in the series of samples containing amorphous phosphate phase (AMP), composite of AMP + nano-structured calcium hydroxyapatite (nano-CaHA) and high-crystalline nano-CaHA were studied under moderate spinning rates (5-30 kHz). The combined analysis of the solid-state 1H and 31P NMR spectra provides the possibility to determine the hydration numbers of the components and the phase composition index. A broad set of spin dynamics models (isotropic/anisotropic, relaxing/non-relaxing, secular/semi-non-secular) was applied and fitted to the experimental CP MAS data. The anisotropic model with the angular averaging of dipolar coupling was applied for AMP and nano-CaHA for the first time. It was deduced that the spin diffusion in AMP is close to isotropic, whereas it is highly anisotropic in nano-CaHA being close to the Ising-type. This can be caused by the different number of internuclear interactions that must be explicitly considered in the spin system for AMP (I-S spin pair) and nano-CaHA (IN-S spin system with N ≥ 2). The P-H distance in nano-CaHA was found to be significantly shorter than its crystallographic value. An underestimation can be caused by several factors, among those - proton conductivity via a large-amplitude motion of protons (O-H tumbling and the short-range diffusion) that occurs along OH- chains. The P-H distance deduced for AMP, i.e. the compound with HPO42- as the dominant structure, is fairly well matched to the crystallographic data. This means that the CP MAS kinetics is a capable technique to obtain complementary information on the proton localization in H-bonds and the proton transfer in the cases where traditional structure determination methods fail.
Collapse
Affiliation(s)
| | - Arūnas Maršalka
- Institute of Chemical Physics, Vilnius University, LT-10257 Vilnius, Lithuania.
| | - Agne Kizalaite
- Institute of Chemistry, Vilnius University, LT-03225, Vilnius, Lithuania
| | - Aleksej Zarkov
- Institute of Chemistry, Vilnius University, LT-03225, Vilnius, Lithuania
| | - Aivaras Kareiva
- Institute of Chemistry, Vilnius University, LT-03225, Vilnius, Lithuania
| | - Kęstutis Aidas
- Institute of Chemical Physics, Vilnius University, LT-10257 Vilnius, Lithuania.
| | - Jérôme Hirschinger
- Institut de Chimie, Université de Strasbourg, UMR 7177 CNRS, Strasbourg, France
| | - Vytautas Balevicius
- Institute of Chemical Physics, Vilnius University, LT-10257 Vilnius, Lithuania.
| |
Collapse
|
3
|
Klimavicius V, Dagys L, Klimkevičius V, Lengvinaitė D, Aidas K, Balčiu̅nas S, Banys J, Chizhik V, Balevicius V. Solid-State NMR and Impedance Spectroscopy Study of Spin Dynamics in Proton-Conducting Polymers: An Application of Anisotropic Relaxing Model. J Phys Chem B 2021; 125:12592-12602. [PMID: 34748346 PMCID: PMC8607415 DOI: 10.1021/acs.jpcb.1c06533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 10/21/2021] [Indexed: 12/04/2022]
Abstract
The 1H-13C cross-polarization (CP) kinetics in poly[2-(methacryloyloxy)ethyltrimethylammonium chloride] (PMETAC) was studied under moderate (10 kHz) magic-angle spinning (MAS). To elucidate the role of adsorbed water in spin diffusion and proton conductivity, PMETAC was degassed under vacuum. The CP MAS results were processed by applying the anisotropic Naito and McDowell spin dynamics model, which includes the complete scheme of the rotating frame spin-lattice relaxation pathways. Some earlier studied proton-conducting and nonconducting polymers were added to the analysis in order to prove the capability of the used approach and to get more general conclusions. The spin-diffusion rate constant, which describes the damping of the coherences, was found to be strongly depending on the dipolar I-S coupling constant (DIS). The spin diffusion, associated with the incoherent thermal equilibration with the bath, was found to be most probably independent of DIS. It was deduced that the drying scarcely influences the spin-diffusion rates; however, it significantly (1 order of magnitude) reduces the rotating frame spin-lattice relaxation times. The drying causes the polymer hardening that reflects the changes of the local order parameters. The impedance spectroscopy was applied to study proton conductivity. The activation energies for dielectric relaxation and proton conductivity were determined, and the vehicle-type conductivity mechanism was accepted. The spin-diffusion processes occur on the microsecond scale and are one order faster than the dielectric relaxation. The possibility to determine the proton location in the H-bonded structures in powders using CP MAS technique is discussed.
Collapse
Affiliation(s)
| | - Laurynas Dagys
- Department
of Chemistry, University of Southampton, SO17 1BJ Southampton, U.K.
| | | | - Dovilė Lengvinaitė
- Institute
of Chemical Physics, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Kęstutis Aidas
- Institute
of Chemical Physics, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Sergejus Balčiu̅nas
- Institute
of Applied Electrodynamics and Telecommunications, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Juras Banys
- Institute
of Applied Electrodynamics and Telecommunications, Vilnius University, LT-10257 Vilnius, Lithuania
| | - Vladimir Chizhik
- Faculty
of Physics, St. Petersburg State University, 198504 St. Petersburg, Russia
| | - Vytautas Balevicius
- Institute
of Chemical Physics, Vilnius University, LT-10257 Vilnius, Lithuania
| |
Collapse
|
4
|
Dagys L, Klimkevičius V, Klimavicius V, Balčiūnas S, Banys J, Balevicius V. Cross‐polarization with magic‐angle spinning kinetics and impedance spectroscopy study of proton mobility, local disorder, and thermal equilibration in
hydrogen‐bonded
poly(methacrylic acid). JOURNAL OF POLYMER SCIENCE 2020. [DOI: 10.1002/pol.20200592] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Laurynas Dagys
- Institute of Chemical Physics Vilnius University Vilnius Lithuania
- Department of Chemistry University of Southampton Southampton UK
| | | | - Vytautas Klimavicius
- Institute of Chemical Physics Vilnius University Vilnius Lithuania
- Eduard‐Zintl Institute for Inorganic and Physical Chemistry University of Technology Darmstadt Darmstadt Germany
| | - Sergejus Balčiūnas
- Institute of Applied Electrodynamics and Telecommunications Vilnius University Vilnius Lithuania
| | - Jūras Banys
- Institute of Applied Electrodynamics and Telecommunications Vilnius University Vilnius Lithuania
| | | |
Collapse
|
5
|
Pestryaev EM. Chain Heterogeneity in Simulated Polymer Melts: NMR Free Induction Decay and Absorption Line. POLYMER SCIENCE SERIES A 2020. [DOI: 10.1134/s0965545x20060097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
6
|
Shenderovich IG. For Whom a Puddle Is the Sea? Adsorption of Organic Guests on Hydrated MCM-41 Silica. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:11383-11392. [PMID: 32900200 DOI: 10.1021/acs.langmuir.0c02327] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Thermal and hydration effects on the mobility of compact and branched organic molecules and a bulky pharmaceutical substance loaded in submonolayer amounts onto mesoporous silica have been elucidated using 1H and 31P solid-state NMR. In all cases, the ambient hydration has a stronger effect than an increase in temperature to 370 K for water-free silica. The effect of hydration depends on the guest and ranges from complete solvation to a silica-water-guest sandwich structure to a silica-guest/silica-water pattern. The mobility of the guests under different conditions has been described. The specific structure of the MCM-41 surface allows one to study very slow surface diffusion, a diffusivity of about 10-15-10-16 m2/s. The data reported are relevant to any nonfunctionalized silica, while the method used is applicable to any phosphor-containing guest on any host.
Collapse
Affiliation(s)
- Ilya G Shenderovich
- Institute of Organic Chemistry, University of Regensburg, Universitaetstrasse 31, 93053 Regensburg, Germany
| |
Collapse
|
7
|
Dagys L, Klimkevičius V, Klimavicius V, Aidas K, Makuška R, Balevicius V. CP MAS kinetics in soft matter: Spin diffusion, local disorder and thermal equilibration in poly(2-hydroxyethyl methacrylate). SOLID STATE NUCLEAR MAGNETIC RESONANCE 2020; 105:101641. [PMID: 31887667 DOI: 10.1016/j.ssnmr.2019.101641] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 12/02/2019] [Accepted: 12/06/2019] [Indexed: 06/10/2023]
Abstract
The 1H-13C cross-polarization magic angle spinning kinetics was studied in poly(2-hydroxyethyl methacrylate) (pHEMA), i.e. a soft material with high degrees of internal freedom and molecular disorder, having the purpose to track the influence of increasing local incoherent contributions to the effects of coherent nature in the open quantum spin systems. The experimental CP MAS kinetic curves were analyzed in the frame of the models of isotropic and anisotropic spin diffusion with thermal equilibration. The rates of spin diffusion and spin-lattice relaxation as well as the profiles of distribution of dipolar coupling, the parameters accounting the effective size of spin clusters and the local order parameters were determined. The intensities of the peaks of periodic quasi-equilibrium origin gradually decrease with increasing disorder, i.e. going from most ordered to more disordered sites in the polymer. Assuming that the thermal motion induced by the temperature gradients is much faster than the equilibration driven by spin diffusion due the difference in spin temperatures, it was deduced that the thermal equilibration in pHEMA occurs in the time scale of 10-4 s. This is one order of magnitude faster than the spectral spin diffusion, which occurs between spins having different resonance frequencies. The thermal equilibration in the case of remote spin clusters was described by the 'stretched exponent' decay. This led to the fractal dimension Dp ≈ 1.65 for both carbon sites (quaternary and carbonyl). The obtained Dp value corresponds to the aggregates, which images are very similar to those for pHEMA and some other related polymer structures are usually conceived.
Collapse
Affiliation(s)
- Laurynas Dagys
- Institute of Chemical Physics, Vilnius University, LT-10257, Vilnius, Lithuania; Department of Chemistry, University of Southampton, SO17 1BJ, Southampton, UK
| | | | - Vytautas Klimavicius
- Institute of Chemical Physics, Vilnius University, LT-10257, Vilnius, Lithuania; Eduard-Zintl Institute for Inorganic and Physical Chemistry, University of Technology Darmstadt, D-64287, Darmstadt, Germany
| | - Kęstutis Aidas
- Institute of Chemical Physics, Vilnius University, LT-10257, Vilnius, Lithuania
| | - Ričardas Makuška
- Institute of Chemistry, Vilnius University, LT-03225, Vilnius, Lithuania
| | - Vytautas Balevicius
- Institute of Chemical Physics, Vilnius University, LT-10257, Vilnius, Lithuania.
| |
Collapse
|
8
|
Dagys L, Klimavicius V, Gutmann T, Buntkowsky G, Balevicius V. Quasi-Equilibria and Polarization Transfer Between Adjacent and Remote Spins: 1H- 13C CP MAS Kinetics in Glycine. J Phys Chem A 2018; 122:8938-8947. [PMID: 30354129 DOI: 10.1021/acs.jpca.8b09036] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The 1H-13C CP MAS kinetic curves were measured in glycine powder sample at the MAS rates of 7, 10, and 12 kHz. Each experimental curve contained up to 1000 equidistant points over the whole contact time range of 10 μs - 10 ms. The CP kinetic data for CH2 group, i.e., for the system containing adjacent 1H-13C spin pairs with a definite dominant dipolar coupling can be described in the frame of the isotropic spin-diffusion approach. The local order parameter ⟨ S⟩ ≈ 1.0, determined as the ratio of the measured dipolar 1H-13C coupling constant and the calculated static dipolar coupling constant, is very close to the values deduced in series of other amino acids. The strong narrow peaks observed in the spin coupling spectrum at multiples of the MAS frequency can be considered as the confirmation that the periodic quasi-equilibrium state can appear also in the powder samples. The anisotropic spin-diffusion approach improved by the introducing of the thermal equilibration in the proton bath is the most proper model to describe the CP kinetics in the system containing remote spins. Very realistic values of the spin-cluster size ( N) have been obtained without any constraint on the flow of the nonlinear curve fitting. The finite values of N ≤ 4 means that CP transfer is located within one glycine molecule.
Collapse
Affiliation(s)
- Laurynas Dagys
- Institute of Chemical Physics , Vilnius University , Sauletekio av. 3 , LT-10257 Vilnius , Lithuania
| | - Vytautas Klimavicius
- Institute of Chemical Physics , Vilnius University , Sauletekio av. 3 , LT-10257 Vilnius , Lithuania.,Eduard-Zintl Institute for Inorganic and Physical Chemistry , University of Technology Darmstadt , Alarich-Weiss-Strasse 8 , D-64287 Darmstadt , Germany
| | - Torsten Gutmann
- Eduard-Zintl Institute for Inorganic and Physical Chemistry , University of Technology Darmstadt , Alarich-Weiss-Strasse 8 , D-64287 Darmstadt , Germany
| | - Gerd Buntkowsky
- Eduard-Zintl Institute for Inorganic and Physical Chemistry , University of Technology Darmstadt , Alarich-Weiss-Strasse 8 , D-64287 Darmstadt , Germany
| | - Vytautas Balevicius
- Institute of Chemical Physics , Vilnius University , Sauletekio av. 3 , LT-10257 Vilnius , Lithuania
| |
Collapse
|
9
|
Pestryaev EM. Oscillating Free Induction Decay in Polymer Systems: Theoretical Analysis. POLYMER SCIENCE SERIES A 2018. [DOI: 10.1134/s0965545x18040090] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|