Dipole Moment Fluctuations Research Articles

Measuring the Magnetic Dipole Moment and Magnetospheric Fluctuations of Accretion-powered Pulsars in the Small Magellanic Cloud with an Unscented Kalman Filter

Many accretion-powered pulsars rotate in magnetocentrifugal disequilibrium, spinning up or down secularly over multiyear intervals. The magnetic dipole moment μ of such systems cannot be inferred uniquely from the time-averaged aperiodic X-ray flux 〈L(t)〉 and pulse period 〈P(t)〉, because the radiative efficiency of the accretion is unknown and degenerate with the mass accretion rate. Here, we circumvent the degeneracy by tracking the fluctuations in the unaveraged time series L(t) and P(t) using an unscented Kalman filter, whereupon μ can be estimated uniquely, up to the uncertainties in the mass, radius, and distance of the star. The analysis is performed on Rossi X-ray Timing Explorer observations for 24 X-ray transients in the Small Magellanic Cloud, which have been monitored regularly for ∼16 yr. As well as independent estimates of μ, the analysis yields time-resolved histories of the mass accretion rate and the Maxwell stress at the disk–magnetosphere boundary for each star, and hence auto- and cross-correlations involving the latter two state variables. The inferred fluctuation statistics convey important information about the complex accretion physics at the disk–magnetosphere boundary.

Research on material jetting fabrication and dielectric constant calculation of LTCC based on silica-borosilicate glass

Several material systems are available for low-temperature co-fired ceramics, and to achieve more efficient designs and applications using additive manufacturing (AM) techniques such as material jetting, the predictability of the dielectric constant of the sintered structure will significantly reduce the consumption of material development. In this work, the LTCC part was fabricated by 3D material jetting using silica-borosilicate glass LTCC ink and densified at 850°C. The borosilicate glass composition was derived from nanopowders prepared by radio frequency plasma spheronisation and configured as surface-grafted glass sols. Scanning electron microscopy results showed that silica particles were embedded in the glass matrix by a liquid phase sintering mechanism accompanied by several confined pores that were difficult to remove. A dielectric constant of around 3.78 was tested from room temperature to 100°C. Molecular dynamics sintering simulation was used to create sintered structures that matched the experimental values. The dipole moment fluctuation of the silica/glass bulk was counted to obtain an accurate value of the dielectric constant, and then the Bruggeman model based on the effective medium theory predicted the dielectric constant of the sintered body, with a prediction of 3.65, which is within 4 % difference from the measured value (3.78). The dielectric constant was predicted for different ceramic/glass compositions and sintering temperatures and found that 35 wt% and 60 wt% should be the upper and lower bounds for borosilicate glass additions to satisfy a stable structure with a relatively low dielectric constant range (3.38–4.42). In conclusion, an effective molecular dynamics approach to predict the dielectric constant of sintered bodies was developed to assist material design in LTCC AM fabrication.

Scalable Analysis of Dipole Moment Fluctuations for Characterizing Intermolecular Interactions and Structural Stability.

Accurately predicting protein-ligand interactions is essential in computational molecular biochemistry and in silico drug development. Monitoring changes in molecular dipole moments through molecular dynamics simulations provides valuable insights into dipole-dipole interactions, which are critical for understanding protein structure stability and predicting protein-ligand binding affinity. In this study, we propose a novel method to monitor changes in the interangle between dipole vectors of residue molecules within proteins and ligand molecules, aiming to evaluate the strength and consistency of interactions within the complex. Additionally, we extend the concept of positional root-mean-square fluctuation (RMSF), commonly used for protein structure stability analysis, to dipole moments, thus defining dipole moment RMSF. This enables us to analyze the stability of dipole moments for each residue within the protein and compare them across residues and between binding and non-binding complexes. Using the CRBP1-retinoic acid complex as our model system, we observed a significant difference in the interangle change of dipole moments for the key residue at the residue-level between the non-binding and binding complexes. Furthermore, we found that the dipole moment RMSF value of the non-binding complex was substantially larger than that of the binding complex, indicating greater dipole moment instability in the non-binding complex. Leveraging the concept of scalability inherent in the calculation of dipole moment vectors, we systematically expanded the residues within the protein's primary secondary structure. Our dipole moment analysis approach can provide valuable predictive insights into complex candidates, especially in situations where experimental comparisons are challenging.

Measuring the Magnetic Dipole Moment and Magnetospheric Fluctuations of SXP 18.3 with a Kalman Filter

The magnetic dipole moment μ of an accretion-powered pulsar in magnetocentrifugal equilibrium cannot be inferred uniquely from time-averaged pulse period and aperiodic X-ray flux data, because the radiative efficiency η 0 of the accretion is unknown, as are the mass, radius, and distance of the star. The degeneracy associated with the radiative efficiency is circumvented if fluctuations of the pulse period and aperiodic X-ray flux are tracked with a Kalman filter, whereupon μ can be measured uniquely up to the uncertainties in the mass, radius, and distance. Here, the Kalman filter analysis is demonstrated successfully in practice for the first time on Rossi X-ray Timing Explorer observations of the X-ray transient SXP 18.3 in the Small Magellanic Cloud (SMC), which is monitored regularly. The analysis yields μ=8.0−1.2+1.3×1030Gcm3 and η0=0.04−0.01+0.02 , compared to μ=5.0−1.0+1.0×1030Gcm3 as inferred traditionally from time-averaged data assuming η 0 = 1. The analysis also yields time-resolved estimates of two hidden state variables, the mass accretion rate and the Maxwell stress at the disk–magnetosphere boundary. The success of the demonstration confirms that the Kalman filter analysis can be applied in the future to study the magnetic moments and disk–magnetosphere physics of accretion-powered pulsar populations in the SMC and elsewhere.

Distance-dependent dielectric constant at the calcite/electrolyte interface: Implication for surface complexation modeling

HypothesisThe electrical double layer formed at the mineral/electrolyte interface is often modeled using mean-field approaches based on a continuum description of the solvent whose dielectric constant is assumed to decrease monotonically with decreasing distance to the surface. In contrast, molecular simulations show that the solvent polarizability oscillates near the surface similar to the water density profile – as shown previously, for example, by Bonthuis et al. (D.J. Bonthuis, S. Gekle, R.R. Netz, Dielectric Profile of Interfacial Water and its Effect on Double-Layer Capacitance, Phys Rev Lett 107(16) (2011) 166102). We showed that molecular and mesoscale pictures agree by spatially averaging the dielectric constant obtained from molecular dynamics simulations over the distances relevant to the mean-field representation. In addition, the values of capacitances used to describe the electrical double layer in Surface Complexation Models (SCMs) of the mineral/electrolyte interface can be estimated using molecularly informed spatially averaged dielectric constants and positions of hydration layers. ExperimentsFirst, we used molecular dynamics simulations to model the calcite 101¯4/electrolyte interface. Next, by using atomistic trajectories, we calculated the distance-dependent static dielectric constant and water density in the direction normal to the. Finally, we applied spatial compartmentalization consistent with the model of parallel-plate capacitors connected in series to estimate SCM capacitances. FindingsComputationally expensive simulations are required to determine the dielectric constant profile of interfacial water near the mineral surface. On the other hand, water density profiles are readily assessable from much shorter simulation trajectories. Our simulations confirmed that dielectric and water density oscillations at the interface are correlated. Here, we parametrized linear regression models to estimate the dielectric constant directly from the local water density. This is a significant computational shortcut compared to slowly converging calculations relying on total dipole moment fluctuations. The amplitude of the interfacial dielectric constant oscillation can exceed the dielectric constant of the bulk water, suggesting an ice-like frozen state, but only if there are no electrolyte ions. The interfacial accumulation of electrolyte ions causes a decrease in the dielectric constant due to the reduction of water density and re-orientation of water dipoles in ion hydration shells. Finally, we show how to use the computed dielectric properties to estimate SCM's capacitances.

Spectroscopic characterization and assessment of microbiological potential of 1,3,4-thiadiazole derivative showing ESIPT dual fluorescence enhanced by aggregation effects

In the presented study, advanced experimental techniques, including electronic absorption and fluorescence spectroscopies [with Resonance Light Scattering (RLS)], measurements of fluorescence lifetimes in the frequency domain, calculations of dipole moment fluctuations, quantum yields, and radiative and non-radiative transfer constants, were used to characterize a selected analogue from the group of 1,3,4-thiadiazole, namely: 4-[5-(naphthalen-1-ylmethyl)-1,3,4-thiadiazol-2-yl]benzene-1,3-diol (NTBD), intrinsically capable to demonstrate enol → keto excited-states intramolecular proton transfer (ESIPT) effects. The results of spectroscopic analyses conducted in solvent media as well as selected mixtures were complemented by considering biological properties of the derivative in question, particularly in terms of its potential microbiological activity. The compound demonstrated a dual fluorescence effect in non-polar solvents, e.g. chloroform and DMSO/H2O mixtures, while in polar solvents only a single emission maximum was detected. In the studied systems, ESIPT effects were indeed observed, as was the associated phenomenon of dual fluorescence, and, as demonstrated for the DMSO: H2O mixtures, the same could be relatively easily induced by aggregation effects related to aggregation-induced emission (AIE). Subsequently conducted quantum-chemical (TD-)DFT calculations supported further possibility of ESIPT effects. The following article provides a comprehensive description of the spectroscopic and biological properties of the analyzed 1,3,4-thiadiazole derivatives, highlighting its potential applicability as a very good fluorescence probes as well as a compound capable of high microbiological activity.

Solvation of small gold clusters in supercritical water

Solvation in supercritical water features fascinating properties such as the selective dissolution or precipitation of non-polar versus polar species. This is known since long to open up astonishing possibilities in organic synthesis, catalysis, or engineering. Less known is the role that supercritical aqueous solutions play close to hydrothermal vents in the deep sea and in ore deposit formation in Earth’s crust. Within this realm, we explore here the solvation of small uncharged gold species, namely the gold dimer and tetramer, in supercritical water in terms of structural and electronic properties using ab initio molecular dynamics simulations. Our simulations reveal that a highly anisotropic first solvation shell is formed around these gold clusters which consists of less than two water molecules on average. Importantly, we find very significant charge transfer and polarization effects between these water molecules and the neutral gold particles, which cannot be captured when using non-polarizable force fields. These electronic many-body effects lead not only to enormous dipole moment fluctuations of the gold clusters themselves, but also to an unexpectedly strong increase of the average effective dipole moments in their first solvation shell. Thus, supercritical solutions of gold particles in water turn out to be surprisingly complex.

Exploring dielectric spectra of polymer through molecular dynamics simulations

ABSTRACT In this work, poly(N-isopropylacrylamide) (PNIPAM) was used as a research object to explore the feasibility of molecular dynamics (MD) simulations to study the dielectric properties of polymers. A comparison of the static dielectric constants for two different calculation schemes, the applied electric field method and the dipole moment fluctuation method, has been conducted. The dielectric properties of PNIPAM aqueous solutions with different concentrations were studied as a function of temperature. The static dielectric constants derived from dipole moment fluctuation method at different temperatures can accurately describe the phase transition process. The concentration does not affect the lower critical solution temperature, but significantly affects the relaxation process of the system. According to the frequency-dependent dielectric constants, two relaxation processes are observed, namely, the dielectric relaxation process in the region of frequency less than 30 terahertz (THz) determined by the synergistic interaction of PNIPAM and water molecules, and that in the region of frequency higher than 30 THz mainly determined by water molecules beyond the solvation shell of the polymer. The calculation results suggest that the dielectric behaviour is concentration and temperature independent, similar to Debye behaviour of bulk water. This method of calculating dielectric properties using MD simulations can be used in detecting the dynamic processes of soft condensed matter and in aiding the design of materials with excellent dielectric properties.

Performance of SI Engine under the Effect of Magnetic Field by using CNG, Petrol and Ethanol

Abstract: The invention resides within the field of treatment of hydrocarbon fuels in liquid or gaseous form, to extend the fuelburning efficiency, by exposing the fuel in containment vessels or conduits to a shaped uniform field of force with a relentless directional flux. Hydrocarbon fuels have long branched geometric chains of carbon atoms which tend to fold over onto themselves and on adjoining molecules because of inter molecular electromagnetic attraction existing between like molecules or atoms. It is vital to grasp that in a very fluid that's subjected to an external field the electron excitation (magnetic moment) occurring, affects molecular orientation. because the axis of the electrons become aligned with the external magnetic flux, the momentum of the molecule not averages intent on zero, as within the normal case in molecules not possessing permanent dipole moments. This accommodation is attributed to the very fact that on the molecular level, a spinning electron subjected to an accurate amount of electromagnetic energy will captivate that energy and "spinflip" into an aligned state. When a magnetism is applied, the instant as seen by the electron excitation, causes the molecule to tend to align with the direction of the field of force. The momentum of the molecule not averages dead set zero because the axis of the electrons aligns with the external magnetic flux, because it does in molecules without permanent dipole moments. The fluctuating dipole moments under the influence of the external flux acquire a net attraction, which produces a stronger bonding with an oxygen ion. As a result of the complex fuel, molecules tend to uncluster, straighten and produce higher combustion efficiencies. the rise in combustion efficiency is because of the unfolding of the hydrocarbon molecules which produce an increased extent for more complete oxidation of the fuel. The unfolding of the fuel molecules is that the major effect of the dipole being off from its neutral state by the applied field of force. Increased combustion yields increased fuel efficiency, with lower hydrocarbon emissions from hydrocarbon-based fuelburning apparatus. However, certain problems remain to be overcome, like whether to focus the force field con or directional alignment, determine flux strength, select appropriate magnetic materials and determine mounting arrangements for the best efficiency. The effect is to stop scaling from occurring on the inner walls of the conduit from the liquid flowing there through by forcing the molecules which might attach themselves to the inner walls of the conduit toward the middle of the conduit. Keywords: The magnetic effect, Combustion, Emissions, paramagnetic, diamagnetic, aligns & orientation, efficiency

Interaction of the new inhibitor paxlovid (PF-07321332) and ivermectin with the monomer of the main protease SARS-CoV-2: A volumetric study based on molecular dynamics, elastic networks, classical thermodynamics and SPT

The COVID-19 pandemic has accelerated the study of drugs, most notably ivermectin and more recently Paxlovid (PF-07321332) which is in phase III clinical trials with experimental data showing covalent binding to the viral protease Mpro. Theoretical developments of catalytic site-directed docking support thermodynamically feasible non-covalent binding to Mpro. Here we show that Paxlovid binds non-covalently at regions other than the catalytic sites with energies stronger than reported and at the same binding site as the ivermectin B1a homologue, all through theoretical methodologies, including blind docking. We volumetrically characterize the non-covalent interaction of the ivermectin homologues (avermectins B1a and B1b) and Paxlovid with the mMpro monomer, through molecular dynamics and scaled particle theory (SPT). Using the fluctuation-dissipation theorem (FDT), we estimated the electric dipole moment fluctuations at the surface of each of complex involved in this study, with similar trends to that observed in the interaction volume. Using fluctuations of the intrinsic volume and the number of flexible fragments of proteins using anisotropic and Gaussian elastic networks (ANM+GNM) suggests the complexes with ivermectin are more dynamic and flexible than the unbound monomer. In contrast, the binding of Paxlovid to mMpro shows that the mMpro-PF complex is the least structurally dynamic of all the species measured in this investigation. The results support a differential molecular mechanism of the ivermectin and PF homologues in the mMpro monomer. Finally, the results showed that Paxlovid despite beingbound in different sites through covalent or non-covalent forms behaves similarly in terms of its structural flexibility and volumetric behaviour.

A universal dielectric constant calculation method for copolymers

In this paper, a method for calculating the dielectric constant of copolymers is proposed, which combines the group contribution (GC) methodand improved dipole moment fluctuation (IDMF) method. The IDMF method is used to calculate the dielectric constant of repeating units. The Vogel model and GC method are used to convert the dielectric constant of the repeating unit to that of the copolymer. The Vogel model is a formula describing the relationship between the molar polarizability, which participates in the calculation in the GC method, and dielectric constant. We selected five typical polymers for the validation of this calculation method and found that the calculation values of IDMF-GC is roughly accurate by comparing it with the experimental values. This new method can be used to calculated the dielectric constant of a new copolymer without the help of experiments. It is of great significance for improving the development efficiency of new block copolymers.

Calculation method for the dielectric constant of thioglycolic acid grafted modified SBS dielectric elastomer

Nonpolar/polar block copolymer materials can be used to develop high-performance dielectric elastomer materials. At present, there is no method to accurately predict its dielectric constant, which is not conducive to improving related research and development efficiency. For this, styrene–butadienestyrene triblock copolymer (SBS) block copolymer grafted modified by thioglycolic acid (TGA) is chosen as the research object. We propose a hybrid calculation method combining the group contribution method, the connectivity index method, and the dipole moment fluctuation method. The connectivity index method and the dipole moment fluctuation method calculate the dielectric constants of nonpolar and polar repeat units to provide accurate basic data for the group contribution method. In the calculation process, the Vogel model completes the mutual conversion between dielectric constant and molar polarizability. Both theoretical calculation and experimental verification show that the dielectric constant of SBS-TGA increases with the grafting rate. We found the correlation between theoretical calculations and experimental values and confirmed that the applicable frequency range of this method is 1 kHz–1000 kHz. This method can be extended to predict the dielectric constant of other polymers and improve development efficiency.

The study of the optical phonon frequency of 3C-SiC by molecular dynamics simulations with deep neural network potential

In this work, we implement molecular dynamics (MD) simulations with deep neural network (DNN) potential trained with the datasets from ab initio calculations to determine the dielectric spectra of crystal. The fluctuations of the total dipole moment of crystal, which are obtained from MD, can be directly related to the frequency-dependent permittivity according to the work of Neumann and Steinhauser [Chem. Phys. Lett. 102, 508–513 (1983)]. We generalize their theoretical work to express the permittivity in the form of a tensor and perform MD simulations for cubic silicon carbide (3C-SiC) with 8000 atoms to assess the accuracy. The infrared resonance frequency and the phonon linewidth obtained by the DNN potential are compared with those obtained by the empirical Vashishta potential and experiments. The results of the DNN potential are in good agreement with the experimental measurements. It shows that we can carry out MD simulations for large systems with the accuracy of ab initio calculations to obtain dielectric properties.

Water Layer at Hydrophobic Surface: Electrically Dead but Dynamically Alive?

The origin of the anomalous low value of the static dielectric constant (SDC) of confined water has been addressed and unearthed. While the low value is partly due to the different dielectric boundaries, a significant role is played by the "electrically dead layer" (EDL). As the observed dielectric constant is the harmonic mean of the grid-wise SDCs, the first layer, having the smallest SDC, makes a disproportionately large contribution. This enhanced contribution, in turn, arises from the orientationally ordered surface water molecules. They exhibit reduced fluctuations in collective dipole moment, as the molecules remain partly caged due to water-surface interactions. This phenomenon is found to be universal. We study the structure and dynamics of the water molecules which characterize the EDL. We demonstrate that while the EDL remains alive at a molecular level, with a finite residence time, it displays time scales not substantially different compared to the distant water layers.

"On-The-Fly" Calculation of the Vibrational Sum-Frequency Generation Spectrum at the Air-Water Interface.

In the present work, we provide an electronic structure based method for the “on-the-fly” determination of vibrational sum frequency generation (v-SFG) spectra. The predictive power of this scheme is demonstrated at the air-water interface. While the instantaneous fluctuations in dipole moment are obtained using the maximally localized Wannier functions, the fluctuations in polarizability are approximated to be proportional to the second moment of Wannier functions. The spectrum henceforth obtained captures the signatures of hydrogen bond stretching, bending, as well as low-frequency librational modes.

Capturing the Effects of Explicit Waters in Implicit Electrostatics Modeling: Qualitative Justification of Gaussian-Based Dielectric Models in DelPhi.

Our group has implemented a smooth Gaussian-based dielectric function in DelPhi (J. Chem. Theory Comput. 2013, 9 (4), 2126-2136) which models the solute as an object with inhomogeneous dielectric permittivity and provides a smooth transition of dielectric permittivity from surface-bound water to bulk solvent. Although it is well-understood that the protein hydrophobic core is less polarizable than the hydrophilic protein surface, less attention is paid to the polarizability of water molecules inside the solute and on its surface. Here, we apply explicit water simulations to study the behavior of water molecules buried inside a protein and on the surface of that protein and contrast it with the behavior of the bulk water. We selected a protein that is experimentally shown to have five cavities, most of which are occupied by water molecules. We demonstrate through molecular dynamics (MD) simulations that the behavior of water in the cavity is drastically different from that in the bulk. These observations were made by comparing the mean residence times, dipole orientation relaxation times, and average dipole moment fluctuations. We also show that the bulk region has a nonuniform distribution of these tempo-spatial properties. From the perspective of continuum electrostatics, we argue that the dielectric "constant" in water-filled cavities of proteins and the space close to the molecular surface should differ from that assigned to the bulk water. This provides support for the Gaussian-based smooth dielectric model for solving electrostatics in the Poisson-Boltzmann equation framework. Furthermore, we demonstrate that using a well-parametrized Gaussian-based model with a single energy-minimized configuration of a protein can also reproduce its ensemble-averaged polar solvation energy. Thus, we argue that the Gaussian-based smooth dielectric model not only captures accurate physics but also provides an efficient way of computing ensemble-averaged quantities.

Broadband electron paramagnetic resonance spectroscopy in diverse field conditions using optically detected nitrogen-vacancy centers in diamond

Paramagnetic magnetic resonance, a powerful technique for characterizing and identifying chemical targets, is increasingly used for imaging; however, low spin polarization at room temperature and moderate magnetic fields poses challenges for detecting small numbers of spins. In this work, we use fluorescence from nitrogen-vacancy (NV) centers in diamond to detect the electron paramagnetic resonance (EPR) spectrum of optically inactive target spins under various conditions of field magnitude and orientation. The protocol requires neither direct microwave manipulation of the NV spins nor spectral overlap between NV and target spin resonances, thus enabling broadband detection. This unexpected non-resonant coupling is attributable to a two-phonon process that relaxes NV spins proximate to the fluctuating dipole moment of the target spin, suggesting that the sensitivity is determined by the dipole–dipole coupling strength. This approach holds promise for sensitive EPR detection, particularly in settings where control over the diamond-crystal orientation is difficult. This is notably the case for biological sensing applications, where nanodiamonds are being pursued for their bright, stable fluorescence and biocompatibility.

Plasmonic Nanocavities Enable Self‐Induced Electrostatic Catalysis

AbstractThe potential of strong interactions between light and matter remains to be further explored within a chemical context. Towards this end herein we study the electromagnetic interaction between molecules and plasmonic nanocavities. By means of electronic structure calculations, we show that self‐induced catalysis emerges without any external stimuli through the interaction of the molecular permanent and fluctuating dipole moments with the plasmonic cavity modes. We also exploit this scheme to modify the transition temperatureT1/2of spin‐crossover complexes as an example of how strong light–matter interactions can ultimately be used to control a materials responses.

Plasmonic Nanocavities Enable Self-Induced Electrostatic Catalysis.

The potential of strong interactions between light and matter remains to be further explored within a chemical context. Towards this end herein we study the electromagnetic interaction between molecules and plasmonic nanocavities. By means of electronic structure calculations, we show that self‐induced catalysis emerges without any external stimuli through the interaction of the molecular permanent and fluctuating dipole moments with the plasmonic cavity modes. We also exploit this scheme to modify the transition temperature T 1/2 of spin‐crossover complexes as an example of how strong light–matter interactions can ultimately be used to control a materials responses.

Unravelling the Composition-Dependent Anomalies of Pair Hydrophobicity in Water-Ethanol Binary Mixtures.

Aqueous binary mixtures have received immense attention in recent years because of their extensive application in several biological and industrial processes. The water-ethanol binary mixture serves as a unique system because it exhibits composition-dependent alteration of dynamic and thermodynamic properties. Our present work demonstrates how different compositions of water-ethanol binary mixtures affect the pair hydrophobicity of different hydrophobes. Pair hydrophobicity is measured by the depth of the first minimum (contact minima) of potential of mean force (PMF) profile between two hydrophobes. The pair hydrophobicity is found to be increased with addition of ethanol to water up to a mole fraction of xEtOH = 0.10 and decreased with further addition of ethanol. This observation is shown to be true for three (methane-methane, isobutane-isobutane, and toluene-toluene) different pairs of hydrophobes. Decomposition of PMF into enthalpic and entropic contribution indicates a switch from entropic to enthalpic stabilization of the contact minimum upon addition of ethanol to water. The gain in mixing enthalpy of the binary solvent system upon association of two hydrophobes is found to be the determining factor for the stabilization of contact minimum. Several static/dynamics quantities (average composition fluctuations, diffusion coefficients, fluctuations in total dipole moment, propensity of ethyl-ethyl association, etc) of the ethanol-water binary mixture also show irregularities around xEtOH = 0.10-0.15. We have also discovered that the hydrogen bonding pattern of ethanol rather than water reveals a change in trend near the similar composition range. As the anomalous behavior of the physical/dynamical properties along with the pair hydrophobicity in an aqueous binary mixture of amphiphilic solutes is a common phenomenon, our results may provide a general viewpoint on these aspects.