Extensive NMRD studies of Ni(II) salt solutions in water and water–glycerol mixtures

Kowalewski, Józef; Egorov, Andrei V.; Kruk, Danuta; Laaksonen, Aatto; Aski, Sahar Nikkhou; Parigi, Giacomo; Westlund, Per‐Olof

doi:10.1016/j.jmr.2008.08.011

Cited by 26 publications

(39 citation statements)

References 47 publications

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“…Measurements of the paramagnetic relaxation enhancement for aqueous proton NMR signal over a broad range of magnetic fields allow a model-dependent estimation of the fluctuations of the ZFS in solution. [70][71][72][73] Simple non-empirical quantum chemical calculations of the ZFS for the hexaaqua-nickel(II) ion were reported long time ago. 13 Also in the 1990s, these calculations were combined with molecular dynamics simulations to generate the timecorrelation function for ZFS fluctuations in aqueous solution of nickel(II) and their consequences for proton relaxation.…”

Section: B Zero Field Splitting In Ni(h 2 O) 6 2+mentioning

confidence: 99%

Zero-field splitting in nickel(II) complexes: A comparison of DFT and multi-configurational wavefunction calculations

Kubica

Kowalewski

Kruk

et al. 2013

The Journal of Chemical Physics

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A consistent and accurate ab initio parametrization of density functional dispersion correction (DFT-D) for the 94 elements H-Pu The Journal of Chemical Physics 132, 154104 (2010) The zero-field splitting (ZFS) is an important quantity in the electron spin Hamiltonian for S = 1 or higher. We report calculations of the ZFS in some six-and five-coordinated nickel(II) complexes (S = 1), using different levels of theory within the framework of the ORCA program package [F. Neese, Wiley Interdiscip. Rev.: Comput. Mol. Sci. 2, 73 (2012)]. We compare the high-end ab initio calculations (complete active space self-consistent field and n-electron valence state perturbation theory), making use of both the second-order perturbation theory and the quasi-degenerate perturbation approach, with density functional theory (DFT) methods using different functionals. The pattern of results obtained at the ab initio levels is quite consistent and in reasonable agreement with experimental data. The DFT methods used to calculate the ZFS give very strongly functional-dependent results and do not seem to function well for our systems.

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Section: B Zero Field Splitting In Ni(h 2 O) 6 2+mentioning

confidence: 99%

Zero-field splitting in nickel(II) complexes: A comparison of DFT and multi-configurational wavefunction calculations

Kubica

Kowalewski

Kruk

et al. 2013

The Journal of Chemical Physics

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“…Even though NMRD data need more parameters, in this case the reorientational correlation time, τ R , and the exchange lifetime, τ M , have been independently estimated. The advantage of starting with the NMRD is not only our previous experience (the slow motion theory has been already used to interpret several relaxation profiles, the work by Kowalewski et al is a recent example 63 ), but also possible difficulties in interpreting in a consistent way the ESR spectra collected at two frequencies.…”

Section: Unified Analysis Of Nmrd and Esr Datamentioning

confidence: 99%

Joint analysis of ESR lineshapes and 1H NMRD profiles of DOTA-Gd derivatives by means of the slow motion theory

Kruk

Kowalewski

Tipikin

et al. 2011

The Journal of Chemical Physics

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The "Swedish slow motion theory" [Nilsson and Kowalewski, J. Magn. Reson. 146, 345 (2000)] applied so far to Nuclear Magnetic Relaxation Dispersion (NMRD) profiles for solutions of transition metal ion complexes has been extended to ESR spectral analysis, including in addition g-tensor anisotropy effects. The extended theory has been applied to interpret in a consistent way (within one set of parameters) NMRD profiles and ESR spectra at 95 and 237 GHz for two Gd(III) complexes denoted as P760 and P792 (hydrophilic derivatives of DOTA-Gd, with molecular masses of 5.6 and 6.5 kDa, respectively). The goal is to verify the applicability of the commonly used pseudorotational model of the transient zero field splitting (ZFS). According to this model the transient ZFS is described by a tensor of a constant amplitude, defined in its own principal axes system, which changes its orientation with respect to the laboratory frame according to the isotropic diffusion equation with a characteristic time constant (correlation time) reflecting the time scale of the distortional motion. This unified interpretation of the ESR and NMRD leads to reasonable agreement with the experimental data, indicating that the pseudorotational model indeed captures the essential features of the electron spin dynamics.

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“…Moreover, the normalized relaxation rates for DF1, DF2 and DF3 follow at low frequencies a linear dependence on ln w over two frequency decades; such a dependence is a marker of 2D translation diffusion. 1 H water relaxation rates in confinement are proportional (after subtracting the contribution to the overall relaxation from bulk water) to the fraction of bound water molecules, providing the exchange lifetime, t ex , between the confined and bulk water pools is sufficiently short, so it can be omitted in the dominator of Equation (7): [38,39] The 2D diffusion suggests that the chains form locally flat surfaces.…”

Section: Resultsmentioning

confidence: 99%

“…The translational correlation time is defined as: [6,7,14,15] where d is referred to as distance of closest approach and can be estimated by the diameter of water molecule (2.75 Å). 1 H water relaxation rates in confinement are proportional (after subtracting the contribution to the overall relaxation from bulk water) to the fraction of bound water molecules, providing the exchange lifetime, t ex , between the confined and bulk water pools is sufficiently short, so it can be omitted in the dominator of Equation (7): [38,39]…”

Section: Resultsmentioning

confidence: 99%

Mechanism of Water Dynamics in Hyaluronic Dermal Fillers Revealed by Nuclear Magnetic Resonance Relaxometry

et al. 2019

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1H spin−lattice nuclear magnetic resonance relaxation experiments were performed for five kinds of dermal fillers based on hyaluronic acid. The relaxation data were collected over a broad frequency range between 4 kHz and 40 MHz, at body temperature. Thanks to the frequency range encompassing four orders of magnitude, the dynamics of water confined in the polymeric matrix was revealed. It is demonstrated that translation diffusion of the confined water molecules exhibits a two‐dimensional character and the diffusion process is slower than diffusion in bulk water by 3–4 orders of magnitude. As far as rotational dynamics of the confined water is concerned, it is shown that in all cases there is a water pool characterized by a rotational correlation time of about 4×10−9 s. In some of the dermal fillers a fraction of the confined water (about 10 %) forms a pool that exhibits considerably slower (by an order of magnitude) rotational dynamics. In addition, the water binding capacity of the dermal fillers was quantitatively compared.

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Extensive NMRD studies of Ni(II) salt solutions in water and water–glycerol mixtures

Cited by 26 publications

References 47 publications

Zero-field splitting in nickel(II) complexes: A comparison of DFT and multi-configurational wavefunction calculations

Zero-field splitting in nickel(II) complexes: A comparison of DFT and multi-configurational wavefunction calculations

Joint analysis of ESR lineshapes and 1H NMRD profiles of DOTA-Gd derivatives by means of the slow motion theory

Mechanism of Water Dynamics in Hyaluronic Dermal Fillers Revealed by Nuclear Magnetic Resonance Relaxometry

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