Energy Moment Research Articles

Electronic and structural properties of fluorene–thiophene copolymers as function of the composition ratio between the moieties: a theoretical study

Through theoretical analysis, we study relevant properties of some molecular structures formed by oligothiophenes (T) and dioctylfluorenes (F) units, commonly employed in the fabrication of different kinds of optical and electronic devices. For so, we first consider F-(T)n-F molecules with different numbers of thiophene rings (n). Among other characteristics, we calculate the dipole moment change between the ground and excited state (Δμge), a quantity that greatly influences the exciton dissociation and charge carrier mobility. We show that the planarity of the ground state geometry correlates Δμge to the exciton binding energy (Eb), with higher Δμge's corresponding to lower Eb's when n > 3. We also unveil a relevant dependence of Δμge with the odd-even parity of n and that Δμge assumes higher values when the molecule is composed by bithiophene (instead of simple thiophenes) moieties in the syn-conformation (with the two heteroatoms pointing in the same direction). From molecules results, we then address larger systems, formed by different oligomers of F-T copolymers containing blocks of dioctylfluorenes and bithiophenes (T2). We systematic investigate their electronic and structural properties as function of the composition ratio between the T2 and F moieties. Similar to the molecules, we deduce that the magnitude of Δμge is higher for the syn conformer of the T2 unit. Moreover, the highest values of Δμge are achieved when the number of the T2 increases relative to a fixed number of the F units in the mer. Such behaviors are in agreement and actually can qualitative explain measurements in the literature on the quantum efficiency of charge carrier generation in F-T copolymers. The present findings can be helpful in designing novel materials with improved photoelectric responses.

A Novel Fault Diagnosis Method Based on Noise-Assisted MEMD and Functional Neural Fuzzy Network for Rolling Element Bearings

To solve the problem in which the auxiliary white-noise parameters need to be artificially selected in a noise-assisted multivariate empirical mode decomposition (NA-MEMD) and considering the fact that obtaining a large number of typical fault samples in practical engineering is difficult, a rolling bearing fault-diagnosis method based on velocity modified-mutation particle swarm optimization (PSO)-optimized NA-MEMD and improved functional neural fuzzy network (FNFN) is proposed. First, the original vibration signal is processed using the velocity modified-mutation PSO–NA-MEMD method to decompose it into a series of intrinsic mode functions (IMFs) with different characteristic time scales. Owing to the distribution characteristics of the IMF with the time scales and because the energy in different states of a bearing in different frequency bands changes, we calculate the energy moment of each IMF as a fault feature vector. Second, the fault feature vectors are then used as input to construct the improved FNFN structure. Finally, the method is validated using the data from the bearing data center of Case Western Reserve University and the vibration signals of the propulsion-motor bearings in the rudder paddle compartment during normal ship navigation and is compared with other neural network. The results show that the method proposed in this paper can quickly and more accurately diagnose rolling-bearing faults using limited training samples.

Potential energy and dipole moment surfaces for HF@C60: Prediction of spectral and electric response properties.

We present a five-dimensional potential energy surface (PES) for the HF@C60 system computed at the DF-LMP2/cc-pVTZ level of theory. We also calculated a five-dimensional dipole moment surface (DMS) based on DFT(PBE0)/cc-pVTZ calculations. The HF and C60 molecules are considered rigid with bond length rHF = 0.9255 Å (gas phase ground rovibrational state geometry). The C60 geometry is of Ih symmetry. The ab initio points were fitted to obtain a PES in terms of bipolar spherical harmonics. The minimum of the PES corresponds to a geometry where the center of mass of HF is located 0.11 Å away from the center of the cage with an interaction energy of -6.929 kcal/mol. The DMS was also represented in terms of bipolar spherical harmonics. The PES was used to calculate the rotation-translation bound states of HF@C60, and good agreement was found relative to the available experimental data [A. Krachmalnicoff et al., Nat. Chem. 8, 953 (2016)] except for the splitting of the first rotational excitation levels. We propose an empirical adjustment to the PES in order to account for the experimentally observed symmetry breaking. The form of that effective PES is additive. We also propose an effective Hamiltonian with an adjusted rotational constant in order to quantitatively reproduce the experimental results including the splitting of the first rotational state. We use our models to compute the molecular volume polarizability of HF confined by C60 and obtain good agreement with experiment.

High-accuracy 12C16O2 line intensities in the 2 µm wavelength region measured by frequency-stabilized cavity ring-down spectroscopy

Reported here are highly accurate, experimentally measured ro-vibrational transition intensities for the R-branch of the (20012)–(00001) 12C16O2 band near λ = 2 µm. Measurements were performed by a frequency-stabilized cavity ring-down spectroscopy (FS-CRDS) instrument designed to achieve precision molecular spectroscopy in this important region of the infrared. Through careful control and traceable characterization of CO2 sample conditions, and through high-fidelity measurements spanning several months in time, we achieve relative standard uncertainties for the reported transition intensities between 0.15 % and 0.46 %. Such high accuracy spectroscopy is shown to provide a stringent test of calculated potential energy and ab initio dipole moment surfaces, and therefore transition intensities calculated from first principles.

Full counting statistics of the subsystem energy for free fermions and quantum spin chains

We calculate the full counting statistics (FCS) of a subsystem energy in free fermionic systems by means of the Grassmann variables. We demonstrate that the generating function of these systems can be written as a determinant formula with respect to the Hamiltonian couplings and by employing the Bell's polynomials, we derive exact formulas for the subsystem energy moments. In addition, we discuss the same quantities in the quantum XY spin chain, and we demonstrate that at the critical regimes the fluctuations of the energy moments decay like a power-law as we expect from the conformal field theory arguments, while in non-critical regimes, the decay is exponential. Furthermore, we discuss the full counting statistics of subsystem energy in the quantum XX chain.

Preparation, single-crystal investigation and spectrophotometric studies of proton transfer complex of 2,6-diaminopyridine with oxalic acid in various polar solvents

Charge transfer complex (CT complex) of donor, 2,6-diaminopyridine (DAP) and π- acceptor, oxalic acid (OA) has been synthesized in acetonitrile at room temperature. The CT complex is formed through the transfer of lone pair electrons from 2,6-diaminopyridine to oxalic acid. The CT complex was characterized by elemental analysis, FTIR spectra single crystal studies, TGA-DTA, 1H NMR and electronic absorption spectra in different solvents which indicate the CT interaction associated with proton migration from the acceptor to the donor followed by hydrogen bonding via N+H⋯O−. It was found that formation of CT Complex is solvent dependent. Spectrophotometric data show the properties of complex in terms of formation constant (KCT), molar extinction coefficient (εCT), energy of interaction (ECT), ionization potential (ID), resonance energy (RN), free energy (ΔG), oscillator strength (f) and transition dipole moment (μEN). The stoichiometry of the CT complex was found to be 1:1 by a straight-line method between donor and acceptor with maximum absorption bands. The physical parameters of CT complex were evaluated by the Benesi–Hildebrand equation. The agreements between the spectroscopic results were also confirmed by single crystal X-ray of the resulting charge transfer complex.

Reactivity of phosphorus mononitride and interstellar formation of molecules containing phospazo linkage: A computational study on the reaction between HSi (X2Π) and PN (X1Σ+)

Phosphorus mononitride (PN) shows some interesting chemistry due to its low dissociation energy (compared to N2) and small dipole moment (zero dipole moment for N2). In this work, a reaction between HSi ([Formula: see text]) and PN ([Formula: see text]) has been studied using various computational methods. Analysis of the doublet surface of the [Formula: see text] reaction indicates that the reaction is exothermic in nature leading to the formation of various products. In view of the barrierless association of the reactants and exothermic nature for the product formation, it is suggested that species like HPNSi, cyclic-SiN(H)P (these two most stable isomers have phosphazo linkage) and HSiNP (third most stable isomer has phosphdiazo linkage) can possibly be detected in the interstellar medium. In view of the potential applications of phosphazo compounds in amide synthesis and pervasive nature of amide linkages in the nature, possible interstellar prebiotic applications can be advocated for these compounds.

Isoscalar E0, E1 , and E2 strength in Ca44

Isoscalar giant resonances in $^{44}\mathrm{Ca}$ have been studied with inelastic scattering of 240 MeV \ensuremath{\alpha} particles at small angles including ${0}^{\ensuremath{\circ}}$. A majority of the energy weighted sum rule was identified for $E0$ and $E2$ ($\ensuremath{\approx}70%$), and nearly half was identified for $E1$. The strength distributions are compared with the predictions from Hartree-Fock based random phase approximation calculations with the KDE0v1 Skyrme-type interaction. The giant monopole resonance energy moments for $^{40,44,48}\mathrm{Ca}$ increase with mass, contrary to what would be expected with a negative symmetry energy, ${K}_{\ensuremath{\tau}}$.

Alteration of gray matter texture features over the whole brain in medication-overuse headache using a 3-dimentional texture analysis

BackgroundImaging studies have provided valuable information in understanding the headache neuromechanism for medication-overuse headache (MOH), and the aim of this study is to investigate altered texture features of MR structural images over the whole brain in MOH using a 3-dimentional texture analysis.MethodsBrain three-dimensional T1-weighted structural images were obtained from 44 MOH patients and 32 normal controls (NC). The imaging processing included two steps: gray matter (gray images) segment and a 3-dimensional texture features mapping. Voxel-based gray-level co-occurrence matrix (VGLCM) was performed to measure the texture parameters mapping including Contrast, Correlation, Energy, Entropy and inverse difference moment (IDM).ResultsThe texture parameters of increased Contrast and Entropy, decreased Energy and IDM were identified in cerebellar vermis of MOH patients compared to NCs. Increased Contrast and decreased Energy were found in left cerebellum. Increased Correlation located in left dorsolateral periaqueductal gray (L-dlPAG), right parahippocampal gyrus (R-PHG), and left middle frontal gyrus (L-MFG) and decreased Correlation located in right superior parietal lobule(R-SPL). Disease duration was positively correlated with Contrast of vermis and negatively correlated with Correlation of R-SPL.HAMD score was negatively correlated with Correlation of R-PHG. MoCA score was positively correlated with Correlation of R-SPL.ConclusionThe altered textures in gray matter related to pain discrimination and modulation, affective and cognitive processing were helpful in understanding the pathogenesis of MOH. Texture analysis using VGLCM is a sensitive and efficient method to detect subtle gray matter changes in MOH.

ExoMol line lists XXIV: a new hot line list for silicon monohydride, SiH

SiH has long been observed in the spectrum of our Sun and other cool stars. Computed line lists for the main isotopologues of silicon monohydride, $^{28}$SiH, $^{29}$SiH, $^{30}$SiH and $^{28}$SiD are presented. These line lists consider rotation-vibration transitions within the ground $X$ $^{2}\Pi$ electronic state as well as transitions to the low-lying $A$ $^{2}\Delta$ and $a$ $^{4}\Sigma^-$ states. Ab initio potential energy (PECs) and dipole moment curves (DMCs) along with spin-orbit and electronic-angular-momentum couplings between them are calculated using the MRCI level of theory with the MOLPRO package. The PEC for the ground X $^2\Pi$ state is refined to available experimental data with a typical accuracy of around 0.01 cm$^{-1}$ or better. The $^{28}$SiH line list includes 11,785 rovibronic states and 1,724,841 transitions with associated Einstein-A coefficients for angular momentum $J$ up to $82.5$ and covering wavenumbers up to 31340 cm$^{-1}$ ($\lambda$ $<$ 0.319 $\mu$m). Spectra are simulated using the new line list and comparisons made with various experimental spectra. These line lists are applicable up to temperatures of ~5000 K, making them relevant to astrophysical objects such as exoplanetary atmospheres and cool stars and opening up the possibility of detection in the interstellar medium. These line lists are available at the ExoMol www.exomol.com and CDS database websites.

α+d→Li6+γ astrophysical S factor and its implications for Big Bang nucleosynthesis

The $\alpha+d\rightarrow\, ^6{\rm Li}+\gamma$ radiative capture is studied in order to predict the $^6$Li primordial abundance. Within a two-body framework, the $\alpha$ particle and the deuteron are considered the structureless constituents of $^6$Li. Five $\alpha+d$ potentials are used to solve the two-body problem: four of them are taken from the literature, only one having also a tensor component. A fifth model is here constructed in order to reproduce, besides the $^6$Li static properties as binding energy, magnetic dipole and electric quadrupole moments, also the $S$-state asymptotic normalization coefficient (ANC). The two-body bound and scattering problem is solved with different techniques, in order to minimize the numerical uncertainty of the present results. The long-wavelength approximation is used, and therefore only the electric dipole and quadrupole operators are retained. The astrophysical $S$-factor is found to be significantly sensitive to the ANC, but in all the cases in good agreement with the available experimental data. The theoretical uncertainty has been estimated of the order of few % when the potentials which reproduce the ANC are considered, but increases up to $\simeq 20$ % when all the five potential models are retained. The effect of this $S$-factor prediction on the $^6$Li primordial abundance is studied, using the public code PArthENoPE. For the five models considered here we find $^6{\rm Li}/$H$ = (0.9 - 1.8) \times 10^{-14}$, with the baryon density parameter in the 3-$\sigma$ range of Planck 2015 analysis, $\Omega_b h^2= 0.02226 \pm 0.00023$.

Theoretical electronic structure of the cadmium monohalide molecules CdX (X = F, Cl, Br, I)

The potential energy and dipole moment curves for the lowest electronic states in the representation 2s+1Λ(±) of CdX (X = F, Cl, Br, I) molecules are investigated via complete active space self-consistent field (CASSCF) and multi-reference configuration interaction MRCI (single and double excitation with Davidson correction). For the bound states of CdX diatomic molecules the bond distances Re, the vibrational harmonic frequencies ωe, the rotational constants Be, the electronic energies relative to the ground state Te, and the permanent and transition dipole moments have been computed. The dissociation energy limits of the atomic levels of CdX compounds are also calculated. The transition dipole moment between the ground state X2Σ+ and (2)2Σ+ is investigated. Consequently, the transition dipole moment values of the upper state at its equilibrium position μ21, the emission angular frequency ω21, the Einstein coefficients of spontaneous and induced emissions (A21 and B21ω), the spontaneous radiative lifetime τspon, the emission cross section σ0, the line strength and the emission oscillator strength f21 are calculated along with the ionicity of the X2Σ+ and (2)2Σ+ states. The eigenvalues Ev, the rotational constants Bv, the centrifugal distortion constants Dv and the abscissas of the turning points Rmin and Rmax of X2Σ+ states of the CdX diatomics are computed. The comparison of the results with those available in literature shows a very good agreement.

Accurate Theoretical Methane Line Lists in the Infrared up to 3000 K and Quasi-continuum Absorption/Emission Modeling for Astrophysical Applications

Abstract Modeling atmospheres of hot exoplanets and brown dwarfs requires high-T databases that include methane as the major hydrocarbon. We report a complete theoretical line list of 12CH4 in the infrared range 0–13,400 cm−1 up to T max = 3000 K computed via a full quantum-mechanical method from ab initio potential energy and dipole moment surfaces. Over 150 billion transitions were generated with the lower rovibrational energy cutoff 33,000 cm−1 and intensity cutoff down to 10−33 cm/molecule to ensure convergent opacity predictions. Empirical corrections for 3.7 million of the strongest transitions permitted line position accuracies of 0.001–0.01 cm−1. Full data are partitioned into two sets. “Light lists” contain strong and medium transitions necessary for an accurate description of sharp features in absorption/emission spectra. For a fast and efficient modeling of quasi-continuum cross sections, billions of tiny lines are compressed in “super-line” libraries according to Rey et al. These combined data will be freely accessible via the TheoReTS information system (http://theorets.univ-reims.fr, http://theorets.tsu.ru), which provides a user-friendly interface for simulations of absorption coefficients, cross-sectional transmittance, and radiance. Comparisons with cold, room, and high-T experimental data show that the data reported here represent the first global theoretical methane lists suitable for high-resolution astrophysical applications.

Ab initio calculations of spectroscopic constants and vibrational state lifetimes of diatomic alkali-alkaline-earth cations.

We investigate the lifetimes of vibrational states of diatomic alkali-alkaline-earth cations to determine their suitability for ultracold experiments where long decoherence time and controllability by an external electric field are desirable. The potential energy and permanent dipole moment curves for the ground electronic states of LiBe+, LiMg+, NaBe+, and NaMg+ are obtained using the coupled cluster with singles doubles and triples and multireference configuration interaction methods in combination with large all-electron cc-pCVQZ and aug-cc-pCV5Z basis sets. The energies and wave functions of all vibrational states are obtained by solving the Schrödinger equation for nuclei with the B-spline basis set method. To predict the lifetimes of vibrational states, the transition dipole moments, as well as the Einstein coefficients describing spontaneous emission, and the stimulated absorption and emission induced by black body radiation are calculated. Surprisingly, in all studied ions, the lifetimes of the highest excited vibrational states are similar to the lifetimes of the ground vibrational states indicating that highly vibrationally excited ions could be useful for the ultracold experiments requiring long decoherence time.

Quantum-Mechanical Prediction of the Averaged Structure, Anharmonic Vibrational Frequencies, and Intensities of the H2O···trans-HONO Complex and Comparison with the Experiment.

The geometrical parameters, the frequencies, and absolute intensities of vibrational transitions of H2O···trans-HONO hydrogen-bonded complex are calculated using the approach earlier tested in calculations of isolated molecules of nitrous acid and complexes of this acid with ammonia. The equilibrium nuclear configuration and potential energy and dipole moment surfaces are calculated by the MP2/aug-cc-pVTZ method with the basis set superposition error taken into account. The fundamental transition frequencies and intensities of the complex are first obtained in the harmonic approximation, and then the energy values, vibrational wave functions, and transition frequencies and intensities are determined from variational solutions of one- to four-dimensional anharmonic equations. The results obtained are compared with the data calculated in the same approximation for an isolated trans-HONO molecule and the NH3···trans-HONO complex. The average discrepancy between the anharmonic frequency values and five available experimental data is 15 cm-1. Three absorption bands of trans-HONO with the highest intensity are recommended for detecting the presence of H2O···trans-HONO.

Electronic structure tuning and band gap opening of nitrogen and boron doped holey graphene flake: The role of single/dual doping

Opening a bandgap in graphene is one of the most important subjects in the graphene research currently, since most of the suggested applications for graphene in field-effect transistors and optoelectronic devices require the ability to adjust its bandgap. To solve this problem, a novel graphene-like nanomaterials, i.e. a nitrogenated holey graphene has been recently synthesized using a simple wet-chemical reaction (Nat. Commun. 2015, 6, 6486). Motivated by this experimental work, in the present study, the structural and electronic properties of the zero dimensional (0D) holey graphene flake are investigated using first-principles calculations. In the framework of density functional theory, we analyze the effects of number of doped atoms (nitrogen and boron) on the structure, stability, and electronic properties of the holey graphene flake. In our survey, we have explored the stability of pristine as well as doped and co-doped holey graphene flake by studding of band gap energy as well as cohesive energy, chemical hardness, hyper-hardness, electrophilicity index, and dipole moment values of the considered flakes. The present study opens the way for manipulating holey graphene and developing promising materials for applications in field-effect transistors and optoelectronic devices.

Ro-vibronic transition intensities for triatomic molecules from the exact kinetic energy operator; electronic spectrum for the C̃ 1B2 ← X̃ 1A1 transition in SO2.

A procedure for calculating ro-vibronic transition intensities for triatomic molecules within the Born-Oppenheimer approximation is reported. Ro-vibrational energy levels and wavefunctions are obtained with the DVR3D suite, which solves the nuclear motion problem with an exact kinetic energy operator. Absolute transition intensities are calculated both with the Franck-Condon approximation and with a full transition dipole moment surface. The theoretical scheme is tested on C̃ 1B2 ← X̃ 1A1 ro-vibronic transitions of SO2. Ab initio potential energy and dipole moment surfaces are generated for this purpose. The calculated ro-vibronic transition intensities and cross sections are compared with the available experimental and theoretical data.

ExoMol molecular line lists – XXIII. Spectra of PO and PS

Comprehensive line lists for phosphorus monoxide ($^{31}$P$^{16}$O) and phosphorus monosulphide ($^{31}$P$^{32}$S) in their $X$ $^2\Pi$ electronic ground state are presented. The line lists are based on new ab initio potential energy (PEC), spin-orbit (SOC) and dipole moment (DMC) curves computed using the MRCI+Q-r method with aug-cc-pwCV5Z and aug-cc-pV5Z basis sets. The nuclear motion equations (i.e. the rovibronic Schr\"odinger equations for each molecule) are solved using the program Duo. The PECs and SOCs are refined in least-squares fits to available experimental data. Partition functions, $Q(T)$, are computed up to $T=$ 5000 K, the range of validity of the line lists. These line lists are the most comprehensive available for either molecule. The characteristically sharp peak of the $Q$-branches from the spin-orbit split components give useful diagnostics for both PO and PS in spectra at infrared wavelengths. These line lists should prove useful for analysing observations and setting up models of environments such as brown dwarfs, low-mass stars, O-rich circumstellar regions and potentially for exoplanetary retrievals. Since PS is yet to be detected in space, the role of the two lowest excited electronic states ($a$ $^4\Pi$ and $B$ $^2\Pi$) are also considered. An approximate line list for the PS $X - B$ electronic transition, which predicts a number of sharp vibrational bands in the near ultraviolet, is also presented. he line lists are available from the CDS (cdsarc.u-strasbg.fr) and ExoMol (www.exomol.com) databases.

Potential energy and dipole moment surfaces of the triplet states of the O2(X3Σg-) - O2(X3Σg-,a1Δg,b1Σg+) complex.

We compute four-dimensional diabatic potential energy surfaces and transition dipole moment surfaces of O2-O2, relevant for the theoretical description of collision-induced absorption in the forbidden X3Σg- → a1Δg and X3Σg- → b1Σg+ bands at 7883 cm-1 and 13 122 cm-1, respectively. We compute potentials at the multi-reference configuration interaction (MRCI) level and dipole surfaces at the MRCI and complete active space self-consistent field (CASSCF) levels of theory. Potentials and dipole surfaces are transformed to a diabatic basis using a recent multiple-property-based diabatization algorithm. We discuss the angular expansion of these surfaces, derive the symmetry constraints on the expansion coefficients, and present working equations for determining the expansion coefficients by numerical integration over the angles. We also present an interpolation scheme with exponential extrapolation to both short and large separations, which is used for representing the O2-O2 distance dependence of the angular expansion coefficients. For the triplet ground state of the complex, the potential energy surface is in reasonable agreement with previous calculations, whereas global excited state potentials are reported here for the first time. The transition dipole moment surfaces are strongly dependent on the level of theory at which they are calculated, as is also shown here by benchmark calculations at high symmetry geometries. Therefore, ab initio calculations of the collision-induced absorption spectra cannot become quantitatively predictive unless more accurate transition dipole surfaces can be computed. This is left as an open question for method development in electronic structure theory. The calculated potential energy and transition dipole moment surfaces are employed in quantum dynamical calculations of collision-induced absorption spectra reported in Paper II [T. Karman et al., J. Chem. Phys. 147, 084307 (2017)].

Textural features of dynamic contrast-enhanced MRI derived model-free and model-based parameter maps in glioma grading.

Presurgical glioma grading by dynamic contrast-enhanced MRI (DCE-MRI) has unresolved issues. The aim of this study was to investigate the ability of textural features derived from pharmacokinetic model-based or model-free parameter maps of DCE-MRI in discriminating between different grades of gliomas, and their correlation with pathological index. Retrospective. Forty-two adults with brain gliomas. 3.0T, including conventional anatomic sequences and DCE-MRI sequences (variable flip angle T1-weighted imaging and three-dimensional gradient echo volumetric imaging). Regions of interest on the cross-sectional images with maximal tumor lesion. Five commonly used textural features, including Energy, Entropy, Inertia, Correlation, and Inverse Difference Moment (IDM), were generated. All textural features of model-free parameters (initial area under curve [IAUC], maximal signal intensity [Max SI], maximal up-slope [Max Slope]) could effectively differentiate between grade II (n = 15), grade III (n = 13), and grade IV (n = 14) gliomas (P < 0.05). Two textural features, Entropy and IDM, of four DCE-MRI parameters, including Max SI, Max Slope (model-free parameters), vp (Extended Tofts), and vp (Patlak) could differentiate grade III and IV gliomas (P < 0.01) in four measurements. Both Entropy and IDM of Patlak-based Ktrans and vp could differentiate grade II (n = 15) from III (n = 13) gliomas (P < 0.01) in four measurements. No textural features of any DCE-MRI parameter maps could discriminate between subtypes of grade II and III gliomas (P < 0.05). Both Entropy and IDM of Extended Tofts- and Patlak-based vp showed highest area under curve in discriminating between grade III and IV gliomas. However, intraclass correlation coefficient (ICC) of these features revealed relatively lower inter-observer agreement. No significant correlation was found between microvascular density and textural features, compared with a moderate correlation found between cellular proliferation index and those features. Textural features of DCE-MRI parameter maps displayed a good ability in glioma grading. 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:1099-1111.