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The possibility of creating a useful model for the electrostatic potential around the water molecule is examined from two different starting points. It is suggested that the simplest and most accurate model will have three point charges on the nuclei together with a diffuse Gaussian charge centered near the nuclear center of the charge. This will represent the lone-pair cloud, include the penetration effects, and improve the representation of the electron density. The alternative use of atomic dipoles is explored but seen to be less effective

A simulation study and experimental data of the CRRES G-9 ionospheric barium release are presented. The simulation study is based on a 2D electrostatic code that incorporates time-dependent coupling to the background plasma. It is shown that the densest portion of the barium ion cloud 'skids' about 15 km within the first three seconds following the release, consistent with the optical data analyses.

An analysis of measurements of electric, magnetic, and radiation field variations produced by rocket-triggered discharges in winter storms in Japan shows that a discharge initiated by a rocket with trailing and grounded wire is a negative leader that consists of continuous current and a pulse series associated with streamer development at the tip. The negative leader is not followed by a process analogous to a return stroke in cloud-to-ground flashes. Application of the electrostatic model of lightning as a bidirectional and uncharged leader in an ambient electric field to analysis of rocket-initiated discharges and positive cloud-to-ground flashes uncovers the commonality of processes occurring in both types of discharges.

The formation of polaron and/or bipolaron species upon chemical doping and photo- or electro-chemical generation is a scientific and technological problem which is still object of discussion. Here we use a simple electrostatic model to study the role of the interchain interaction in stabilizing or destabilizing the bipolaronic structure, which is usually neglected in theoretical studies. The results show that, as a consequence of the interchain interactions in the bulk system, a bipolaron generated on a single oligomer chain more than 12 units long will soon split into two polarons on adjacent chains, this process being maximized for specific interchain distances.

A group theoretical parametrization scheme of the bilinear orbit-lattice interaction is presented. Using this scheme a general analytical form of this interaction in the point-charge electrostatic model has been obtained. Based on this general analytical form the second-order parameters of the bilinear orbit-lattice interaction have been calculated for a tetrahedral complex. For cubic complexes a microscopic interpretation of the G-tensor components in the long-wavelength approximation of acoustic waves is given for the first time. The presented scheme of parametrization as well as the method of calculations of the interaction parameters may be extended to other models of the crystal field.

Using three different methods we tried to compute 171 experimentally known pK(a) values of ionizable residues from 15 different proteins and compared the accuracies of computed pK(a) values in terms of the root mean square deviation (RMSD) from experiment. One method is based on a continuum electrostatic model of the protein including conformational flexibility (KBPLUS). The others are empirical approaches with PROPKA deploying physically motivated energy terms with adjustable parameters and PKAcal using an empirical function with no physical basis. PROPKA reproduced the pK(a) values with highest overall accuracy. Differentiating the data set into weakly and strongly shifted experimental pK(a) values, however, we found that PROPKA's accuracy is better if the pK(a) values are weakly shifted but on equal footing with that of KBPLUS for more strongly shifted values. On the other hand, PKAcal reproduces strongly shifted pK(a) values badly but weakly shifted values with the same accuracy as PROPKA. We tested different consensus approaches combining data from all three methods to find a general procedure for most accurate pK(a) predictions. In most of the cases we found that the consensus approach reproduced experimental data with better accuracy than any of the individual methods alone.

We present a strategy for comparing the global properties of competing potential models. By systematically sampling the potential energy surface of crystalline tetracene, we assess how the number, energy and structure of its minima are modified by switching on (or off) the Coulombic interactions. The increased complexity of the Coulombic potential leads to a more "rugged" potential energy surface with a larger number of minima, but the effect is not large. In fact, we find a subset of minima stable only in presence of the Coulombic interactions, a smaller subset stable only in their absence, and a large majority stable in both cases. Among these, there is a very good, but not perfect, correlation between the energies and the structures computed with and without the electrostatic interactions. Although electrostatic interactions play a role even in a rigid nonpolar molecule such as tetracene, they are not as crucial as often believed, because altering the electrostatic model (or switching it off completely) leads, in most cases, to equivalent results.

We present 47,49Ti and 135,137Ba NMR second-order quadrupolar rotation patterns in a tetragonal single domain crystal of BaTiO3. These data will be analysed in terms of a ionic polarizable point multipole model.

Madelung potentials are calculated for several choices of formal oxidation states of the ions in the high temperature superconductor YBa2Cu3O7. For p-type CuO2 planes a slightly lower energy is found for a lattice with holes localised on copper (Cu3+) than for one with holes on oxygen (O−). Moreover, for the lattice with oxygen holes there is a negative energy for electron transfer between neighbouring Cu2+ O− sites. The near degeneracy of the ‘copper hole’ and ‘oxygen-hole’ lattices suggests that they should be strongly mixed and this may play some role in the superconductivity behaviour. Fur eine Auswahl von formalen Oxydationszustanden der Ionen im Hochtemperatursupraleiter YBa2Cu3O7 werden die Madelungpotentiale berechnet. Fur p-Typ-CuO2-Ebenen wird eine leicht niedrigere Energie gefunden fur ein Gitter, bei dem die Locher am Kupfer (Cu3+) lokalisiert sind, als fur ein Gitter mit Lochern am Sauerstoff (O−). Daruber hinaus existiert fur das Gitter mit Sauerstoff-Lochern eine negative Energie fur den Elektronentransfer zwischen benachbarten Cu2+ -O-Platzen. Die Fast-Entartung der „Kupferloch” - und „Sauerstoff-Loch” -Gitter weist darauf hin, das sie stark gemischt sein konnen und dies eine Rolle im Supraleitungsverhalterhalten spielen kann.

GaAsAlAs multiquantum wells having a thin AlAs spike in the middle of each well have been studied by resonant Raman scattering. Transitions to both Γ-like and X-like conduction bands are observed. AlAs- and GaAs-like interface modes (IF) have also been observed, whose frequency changes with the spike width. This effect is explained by a generalized electrostatic model for IF modes. Finally, the AlAs LO1 mode confined in the spike has been observed, showing a resonance at electronic transitions of the GaAs wells.

Empirical potentials are proposed to simulate benzene and an excess electron in liquid benzene. The benzene-benzene potential is closely modelled on another that has previously been well tested in the condensed phase. We have improved the electrostatic model of benzene, and to be consistent we have used the same representation for both potentials. The electron-benzene potential is derived in part using ideas from density functional theory, and the principles could equally well be applied to other electron-molecule systems. The electron is found to be repelled from the benzene, except in a few regions of space, mainly close to the molecular plane.

The formation of triple-stranded nucleic acid helices is studied by molecular mechanics and molecular dynamics calculations. Using standard TAT and CGG homopolymers, single, triple, and quintuple molecular replacements are made. Some of these replacements are expected to form Hoogsteen bonds and some are not. While the electrostatic and total energetic differences for base triplet mismatches were dependent on the electrostatic model chosen, clear trends in the local geometric distortions were apparent. Relationships between these model-built strand geometries and chemical probe experiments are discussed.

A new approach to the old idea of deriving a bond-valence vector from the well-known bond-valence concept has been proposed. The foundation of the proposal is the previous electrostatic model in which bond valences are interpreted as electric fluxes. The outcome of this approach is actual vectorial quantities whose magnitudes are strictly but nonlinearly related to the scalar bond valences and are directed along the bond lines. It has been proved that the sum of all these bond-valence vectors drawn from a coordination center to its ligating atoms will be close to zero for the complete coordination sphere. Therefore, unlike the scalar bond valences, the obtained vectors provide information about the spatial arrangement of ligands. The geometrical consequences of the proposed bond-valence vector (BVV) model are analyzed for the geometries of the carbonates, phosphates, and five-coordinated organoaluminum compounds with CO3, PO4, and AlCO4 skeletons, respectively, retrieved from the Cambridge Structural Database. For acyclic carbonates this BVV model allows one to predict the O-C-O angles with a mean absolute error of 1.0 degrees using the empirical C-O distances only. Furthermore, this BVV model is able to quantitatively describe the strains in cyclic carbonates. The preliminary studies for NO2E, PO3E, and SO3E systems with a strongly stereoactive lone electron pair (E) show that the model may serve as a quantitative description of the lone electron pair effect on the coordination sphere. A great advantage of the presented BVV approach is that the derived relation between a bond-valence vector, bond valence, and bond length is given by an uncomplicated equation allowing quick and simple computations, thus providing a new analytical tool for describing the geometry of a coordination sphere that may be applied for structure validation.

We report strong even-odd effects in multiple ionization yields of van der Waals dimers in slow ${\mathrm{Xe}}^{30+}+[{\mathrm{C}}_{60}{]}_{2}([{\mathrm{C}}_{60}{\mathrm{C}}_{70}])\ensuremath{\rightarrow}\ensuremath{\cdots}+{[{\mathrm{C}}_{60}{]}_{2}}^{r+}({[{\mathrm{C}}_{60}{\mathrm{C}}_{70}]}^{r+})$ electron-transfer collisions as functions of $r\ensuremath{\le}7$. This behavior may be due to even-odd variations in the sequences of dimer ionization energies as calculated with an electrostatic model including an electrical fullerene-fullerene contact at the $19{a}_{0}$ center-center separation in ${[{\mathrm{C}}_{60}{]}_{2}}^{+}$. Prompt dissociations predominantly yield intact fullerenes ${[{\mathrm{C}}_{60}{]}_{2}}^{r+}\ensuremath{\rightarrow}{{\mathrm{C}}_{60}}^{{r}_{1}+}+{{\mathrm{C}}_{60}}^{{r}_{2}+}$ in the same (${r}_{1}={r}_{2}$, even $r$) or nearby (${r}_{1}={r}_{2}\ifmmode\pm\else\textpm\fi{}1$, odd $rg1$) charge states.

We are testing the idea that placement of fixed charges near one face of the DNA double helix can induce DNA bending by a purely electrostatic mechanism. If stretching forces between DNA phosphates are significant, fixed charges should induce DNA bending by asymmetrically modulating these forces. We have previously tested this hypothesis by adding charged residues to small bZIP DNA binding peptides and monitoring DNA bending using electrophoretic phasing assays. Our results were consistent with an electrostatic model of DNA bending in predicted directions. We now confirm these observations with fluorescence resonance energy transfer (FRET). Using a "U"-shaped DNA probe, we report that DNA bending by charged bZIP peptides is readily detected by FRET. We further show that charged bZIP peptides cause DNA bending rather than DNA twisting.

The arsenal of drugs in the fight against AIDS is rapidly diminishing as the HIV becomes resistant to the available reverse transcriptase and protease inhibitors. After killing millions all over the world, the virus is still on the rampage and hence the pharmaceutical industry is resorting to the development of inhibitors of integrase. This seems to be the last arrow in the quiver of potential drug leads to combat the deadly infection. Several classes of HIV integrase inhibitors have been reported to date; however, none is clinically useful. This review details the existing knowledge of the biological functions of the HIV-1 integrase with the focus on its available inhibitors, their disadvantages, and the current trends in designing novel compounds as anti-integrase.

Approaches for the prediction of transport of radioactive species in underground and surface water based on experimentally determined distribution coefficients (Kd) and sorption isotherms have a limited predictive capability, due to their sensitivity to many parameters. Models based on thermodynamic equilibrium can account for the influence of multiple parameters, but show important theoretical and experimental limitations, which restrict their predictive character for transport calculation.

Three-dimensional quantitative structure–activity relationship (3D QSAR) modeled for α-asarone derivatives using the comparative molecular surface analysis (CoMSA) allowed us to reveal a correlation between the activity of these compounds and the electrostatic potential at the molecular surface. The grid formalism (s-CoMSA) allowed us to indicate a pharmacophore that is of key importance for compound activity. The CoMSA formalism coupled with the iterative variable elimination method gives a highly predictive model.

A new silicon detector for upgrading of DELPHI tracking in the forward region was developed. Due to space restrictions, the hybrids with the readout chips were placed directly on the detectors. The two different types of readout chips (Viking, MX-6) were used for signal readout in the prototype tests. An optimized hybrid design was required to reduce pick-up on the detector strips. The charge loss for hits on the intermediate strips was measured in the test beam and with a light source, as well as calculated from the electrostatic model.

Using a model potential which combines the spherically averaged Girifalco potential and a point polarizable dipole electrostatic model, we computed the ground-state structures of singly ionized clusters of C60 molecules and compared the results with predictions derived for neutral C60 clusters using Girifalco’s potential. The structures of the simulated ionized fullerene clusters were similar to those of the corresponding neutral clusters, in keeping with the conclusions inferred recently by Branz et al. [Phys. Rev. B 66, 094107 (2002)] from time-of-flight mass spectrometry experiments. © 2004 The American Physical Society.

The complexation between Th(IV) and acetate in 1.05 mol kg(-1) NaClO4 was studied at variable temperatures (10, 25, 40, 55 and 70 degrees C). The formation constants of five successive complexes, Th(Ac)j(4-j)+ where Ac = CH3COO- and j = 1-5, and the molar enthalpies of complexation were determined by potentiometry and calorimetry. Extended X-ray absorption fine structure spectroscopy (EXAFS) provided additional information on the complexes in solution. The effect of temperature on the stability of the complexes is discussed in terms of the electrostatic model.

A series of oxygenated chalcones which have been evaluated earlier for antimalarial activity (Plasmodium falciparum K1) were tested for antileishmanial activity against Leishmania donovani amastigotes. A comparison of structure-activity relationships reveal that different physicochemical and structural requirements exist for these two activities. Antileishmanial activity is associated with less lipophilic chalcones, in particular those with 4'-hydroxyl-substituted B rings and hetero/polyaromatic A rings. In contrast, chalcones with good antimalarial activity have alkoxylated B rings and electron-deficient A rings. Visualization of the steric and electrostatic fields generated from comparative molecular field analysis (CoMFA) indicate that the ring A of chalcones make a more significant contribution to antileishmanial activity while both rings A and B are important for antimalarial activity. Despite different requirements, two alkoxylated chalcones (8, 19) were identified which combined good antimalarial and antileishmanial activities.

To provide an objective QSAR methodology that might accelerate lead optimization, the CoMFA and topomer technologies have been merged, with surprisingly good results. A series of input structures are each broken into two or more fragments at central acyclic single bonds, while removing any core fragment structurally common to the entire series. Standard topomer 3D models are automatically constructed for each fragment, and a set of steric and electrostatic fields ("CoMFA column") is generated for each set of topomers. Application of "topomer CoMFA" to 15 3D-QSAR analyses taken from the literature (847 structures) were all successful, with an average q(2) of 0.520 (literature average q(2) = 0.636) and an average standard deviation of true prediction (SDEP) of 0.688 (literature average SDEP = 0.553) for 133 structures. Topomer CoMFA results are particularly promising as queries into virtual libraries already composed of topomer structures, to directly seek structures having increased potency. Accordingly, in 13 of the 15 such "topomer CoMFA searches" attempted, combinations of commercially offered fragments were retrieved that were predicted to be more potent than any structure described in the original publication (average predicted potency increase = 20 x), showing in principle how optimization could occur.

In this paper, a electrostatic model has been used to calculate the spatial and temporal development of partial discharges in a pre-defined electrical tree. The aim was to bring together our various detection techniques (partial discharge detector, capacitor bridge and charge coupled device imaging) under a common theoretical framework.

We report a detailed study of the vibrational properties of BN single-walled nanotubes and of the BN monolayer. Our results have been obtained from a well-established tight-binding model complemented with an electrostatic model to account for the long-range interactions arising from the polar nature of the material and which are not included in the tight-binding model. Our study provides a wealth of data for the BN monolayer and nanotubes, such as phonon band structure, vibrational density of states, elastic constants, etc. For the nanotubes we obtain the behavior of the optically active modes as a function of the structural parameters, and we compare their frequencies with those derived from a zone-folding treatment applied to the phonon frequencies of the BN monolayer, finding general good agreement between the two., This work was supported in part by the Spanish Ministerio de Ciencia y Tecnologia Grant Nos. MAT2001-0946, BFM2000-1312-C02, and BFM2002-03278 and by the Basque Departamento de Educacion, Universidades e Investigacion, and the University of the Basque Country UPV/EHU Grant No. 9/UPV 00206.215-13639/ 2001. D.S.P. acknowledges support from the Spanish Ministerio de Ciencia y Tecnologia and CSIC under the ‘‘Ramon y Cajal’’ program. E.H. thanks the IST project SATURN IST-1999-10593.

The densities of commercial Nafion 117 and cast Nafion 1100 films were determined by the hydrostatic weighing method for films fully exchanged with hexaammineruthenium(III), tris(2,2' bipyridyl)ruthenium(II), tetramethylammonium, ferrous, and hydrogen ions. Films were pretreated in either water or concentrated nitric acid prior to cation exchange. All densities ranged between 1.65 and 2.19 g/cm3. Excluding the proton-exchanged films, the average density is 1.90 +/- 0.14 g/cm3, well in excess of the 1.58 g/cm3 commonly employed for Nafion. The density of acid-pretreated Nafion 1100 was constant at 1.95 +/- 0.03 g/cm3 for all cations except the proton. A simple, empirical model based on the Coulombic interaction between the intercalated cation and the sulfonate sites of the Nafion characterizes density for the commercial Nafion 117 films. A modified version of the model is appropriate for water-treated Nafion 1100. Water content of the films and implications for characterizing modified electrodes are discussed.

A new method for considering solvation when calculating electrostatics for protein docking is proposed. The solvent-exposed charges are attenuated by induced solvent polarization charges. Modified charges are pre-calculated and the correction doesn't affect the speed of the actual simulation. The new Screened Charge Electrostatic Model (SChEM) results in an improved discrimination of near-native solutions from false positives in docking simulations as compared to conventional 'non-solvated' charge assignment. A series of protein-protein complexes were analyzed by running automated rigid-body Monte-Carlo docking simulations using the 3-D coordinates of the unbound components. In all but one case, the use of solvation screened charges for electrostatic calculations helped to improve the rank of the near-native solution after rigid-body simulations. The SChEM also drastically improved the results of the subsequent refinement of the interface side-chains. In all cases the final lowest energy solution was found within 3.0 A r.m.s.d. of the crystal structure.

The approximations within the Judd-Ofelt theory are eliminated by an explicit reformulation of the absorption amplitude for $f\ensuremath{\leftrightarrow}f$ dipole transitions in terms of determinantal product states and perturbed functions. By considering the crystal-field and spin-orbit perturbations we obtain expressions for amplitudes of the type $〈{\ensuremath{\varphi}}_{\mathrm{cf}}^{1}|{d}_{q}^{1}|{\ensuremath{\varphi}}^{0}〉,$ $〈{\ensuremath{\varphi}}_{\mathrm{cf}}^{1}|{d}_{q}^{1}|{\ensuremath{\varphi}}_{\mathrm{so}}^{1}〉,$ and $〈{\ensuremath{\varphi}}_{\mathrm{cf}}^{1}|{d}_{q}^{1}|{\ensuremath{\varphi}}_{\mathrm{cf}}^{1}〉.$ The latter two are third-order results, going beyond the standard Judd-Ofelt theory. There are no experimentally fitted parameters used in the amplitude calculations. Crystal-field parameters ${A}_{\mathrm{tp}}$ needed for the intensity calculations are calculated using the self-consistent electrostatic model. Polarized absorption spectra are calculated for ${\mathrm{Nd}}^{3+},$ ${\mathrm{Ho}}^{3+},$ ${\mathrm{Er}}^{3+},$ or ${\mathrm{Tm}}^{3+}$ in ${\mathrm{LiYF}}_{4}.$ Very good agreement with experiment is, in general, observed. The contribution from the third-order terms $〈{\ensuremath{\varphi}}_{\mathrm{cf}}^{1}|{d}_{q}^{1}|{\ensuremath{\varphi}}_{\mathrm{so}}^{1}〉$ and $〈{\ensuremath{\varphi}}_{\mathrm{cf}}^{1}|{d}_{q}^{1}|{\ensuremath{\varphi}}_{\mathrm{cf}}^{1}〉$ are seen to be small in comparison with $〈{\ensuremath{\varphi}}_{\mathrm{cf}}^{1}|{d}_{q}^{1}|{\ensuremath{\varphi}}^{0}〉.$

The pK 1 and pK 2 values of malic, malonic, maleic, succinic, tartaric, and phthalic acids have been determined in ethane-1,2-diol-water media of varying solvent compositions (0-50 wt % ethane-1,2-diol) within the temperature range (25-65°C). An extrathermodynamic analysis of the obtained results have been examined, in the light of ΔH°-ΔS° relationship. The pK values have been correlated with the relative permittivity of the medium according to Born's electrostatic model.

A comparative study between a relative experimental scale of electrophilicity and a theoretical absolute scale based on electronic reactivity indexes is presented. The theoretical scale correctly predicts the experimentalelectrophilicity within the dihalogen and inter-halogen subseries (XY) including F 2 , Cl 2 , Br 2 , BrCl, and ClF and the HX (X = F, Cl, Br) series. It is shown that the best correlation is obtained for the local electrophilic index that encompasses the global electrophilicity power weighted by a local factor described by the electrophilic Fukui function. This result is in agreement with the electrostatic model of Legon (Angew. Chem., Int. Ed. Engl. 1999, 38, 2686), as the electrophilic power of molecules is mainly determined by the local properties of the electrophilic ends of HX and XY species. We also evaluated the electrophilicity of Li 2 , LiH, LiF, and LiCl species for which experimental data are not available. Whereas LiH is predicted to have an electrophilic potential comparable to that shown by the dihalogen and inter-halogen series but higher than that of the HX species, LiF and LiCI are predicted to display an electrophilic pattern even higher that those of the XY and HX molecules. On the other hand, Li 2 displays an electrophilic pattern even lower than that of F 2 .

Some phenomena induced by placing an electrode at the center of a cylindrical apparatus confining ions or electrons, such as magnetic and electrodynamic traps, are analyzed on the basis of an electrostatic model. It is show that a purely two-dimensional system of charges can be formed on a cylindrical surface under appropriate conditions

We present the analysis of a simple electrostatic model of a solid-state capacitor with ionizable charge traps. It shows a charge–voltage characteristic resembling a chemical battery. With a given withstanding voltage and the same geometry, the energy density of the capacitor with ionizable traps will be lower than that of an ordinary capacitor with metal electrodes.

A CoMFA study of artemisinin derivatives with changes of the location and the number of lattice points was performed. The location of probe atoms in a large lattice has practically no effect on the cross-validated r 2 value (r 2 cv ). The selection of only 18 probe atoms around the peroxide bond, considering the action mechanism of artemisinin, provided a less time-demanding and more reliable CoMFA model, which forecasts better than the large lattice model despite the lower r 2 cv value. Only 1 A displacement of the small lattice caused a reduction of cross-validated r 2 value of more than 50%, which indicates the lattice location played an important role in this small lattice model.

Arc repressor forms a homodimer in which the subunits intertwine to create a single globular domain. To obtain Arc sequences that fold preferentially as heterodimers, variants with surface patches of excess positive or negative charge were designed. Several but not all oppositely charged sequence pairs showed preferential heterodimer formation. In the most successful design pair, α helix B of one subunit contained glutamic acids at positions 43, 46, 47, 48, and 50, whereas the other subunit contained lysines or arginines at these positions. A continuum electrostatic model captures many features of the experimental results and suggests that the most successful designs include elements of both positive and negative design.

Quantitative structure activity relations (QSAR), and three-dimensional quantitative structure-activity relations (3D-QSAR) have had a profound impact on medicinal chemistry [1–6]. The ability to produce quantitative correlations between three-dimensional properties of molecules and the biological activity of these compounds is of inestimable value in deciding upon the choice of future synthetic chemistry.

Atomic force microscopy (AFM) is a mechanical profiling technique that allows to image surfaces with atomic resolution. Recent progress in reducing the noise of this technique has led to a resolution level where previously undetectable symmetries of the images of single atoms are observed. These symmetries are related to the nature of the interatomic forces. The Si(111)-(7x7) surface is studied by AFM with various tips and AFM images are simulated with chemical and electrostatic model forces. The calculation of images from the tip-sample forces is explained in detail and the implications of the imaging parameters are discussed. Because the structure of the Si(111)-(7x7) surface is known very well, the shape of the adatom images is used to determine the tip structure. The observability of atomic orbitals by AFM and scanning tunneling microscopy is discussed., 21 pages, 17 figures

This chapter presents some insights into the modeling of different Multi-Gate SOI MOSFET structures, and in particular Double-Gate MOSFETs (DG MOSFETs) and Tri-Gate MOSFETs (TGFETs). For long-channel case an electrostatic model can be developed from the solution of the 1D Poisson's equation (in the case of DG MOSFETs) and the 2D Poisson's equation in the section perpendicular to the channel (in the case of TGFETs). Allowing it to be incorporated in quasi-2D compact models. For short-channel devices a model can be derived from a 2D (in the case of DG MOSFETs) or a 3D (in the case of TGFETs) electrostatic analysis. The models were successfully compared with 2D and 3D TCAD simulations and, in some cases, experimental measurements. Short-channel effects, such as subthrehold slope degradation, threshold voltage roll-off and DIBL were accurately reproduced.