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Angela K Wilson - One of the best experts on this subject based on the ideXlab platform.
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Behavior of the Sapporo-nZP-2012 Basis set family
Chemical Physics Letters, 2015Co-Authors: Rebecca Weber, Benjamin Hovda, George Schoendorff, Angela K WilsonAbstract:Abstract The behavior of Sapporo- n ZP-2012 ( n = D, T, Q) Basis sets for 3 d atoms is investigated. It is shown that total atomic energies obtained using Sapporo sets of increasing quality converge to a limit. Several schemes are used to determine these limits and comparisons are made to numerical Hartree–Fock energies and to limits obtained with correlation Consistent sets (cc-pV n Z, n = T, Q, 5). While differences in energy relative to numerical HF are larger for Sapporo- n ZP-2012 sets (16–40 mE h ) than for correlation Consistent Basis sets (∼0.005 mE h ), the systematic nature of the Sapporo- n ZP-2012 sets may provide a reasonable alternative when the correlation Consistent Basis sets are not available.
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correlation Consistent Basis sets for the atoms in xe
Journal of Chemical Physics, 2015Co-Authors: Andrew Mahler, Angela K WilsonAbstract:In this work, the correlation Consistent family of Gaussian Basis sets has been expanded to include all-electron Basis sets for In–Xe. The methodology for developing these Basis sets is described, and several examples of the performance and utility of the new sets have been provided. Dissociation energies and bond lengths for both homonuclear and heteronuclear diatomics demonstrate the systematic convergence behavior with respect to increasing Basis set quality expected by the family of correlation Consistent Basis sets in describing molecular properties. Comparison with recently developed correlation Consistent sets designed for use with the Douglas-Kroll Hamiltonian is provided.
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Correlation Consistent Basis sets for the atoms In–Xe
Journal of Chemical Physics, 2015Co-Authors: Andrew Mahler, Angela K WilsonAbstract:In this work, the correlation Consistent family of Gaussian Basis sets has been expanded to include all-electron Basis sets for In–Xe. The methodology for developing these Basis sets is described, and several examples of the performance and utility of the new sets have been provided. Dissociation energies and bond lengths for both homonuclear and heteronuclear diatomics demonstrate the systematic convergence behavior with respect to increasing Basis set quality expected by the family of correlation Consistent Basis sets in describing molecular properties. Comparison with recently developed correlation Consistent sets designed for use with the Douglas-Kroll Hamiltonian is provided.
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vibrational frequency scale factors for density functional theory and the polarization Consistent Basis sets
Journal of Computational Chemistry, 2012Co-Authors: Marie L Laury, Matthew J Carlson, Angela K WilsonAbstract:Calculated harmonic vibrational frequencies systematically deviate from experimental vibrational frequencies. The observed deviation can be corrected by applying a scale factor. Scale factors for: (i) harmonic vibrational frequencies [categorized into low ( 1000 cm−1)], (ii) vibrational contributions to enthalpy and entropy, and (iii) zero-point vibrational energies (ZPVEs) have been determined for widely used density functionals in combination with polarization Consistent Basis sets (pc-n, n = 0,1,2,3,4). The density functionals include pure functionals (BP86, BPW91, BLYP, HCTH93, PBEPBE), hybrid functionals with Hartree-Fock exchange (B3LYP, B3P86, B3PW91, PBE1PBE, mPW1K, BH&HLYP), hybrid meta functionals with the kinetic energy density gradient (M05, M06, M05-2X, M06-2X), a double hybrid functional with Moller-Plesset correlation (B2GP-PLYP), and a dispersion corrected functional (B97-D). The experimental frequencies for calibration were from 41 organic molecules and the ZPVEs for comparison were from 24 small molecules (diatomics, triatomics). For this family of Basis sets, the scale factors for each property are more dependent on the functional selection than on Basis set level, and thus allow for a suggested scale factor for each density functional when employing polarization Consistent Basis sets (pc-n, n = 1,2,3,4). A separate scale factor is recommended when the un-polarized Basis set, pc-0, is used in combination with the density functionals. © 2012 Wiley Periodicals, Inc.
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harmonic vibrational frequencies scale factors for pure hybrid hybrid meta and double hybrid functionals in conjunction with correlation Consistent Basis sets
Journal of Computational Chemistry, 2011Co-Authors: Marie L Laury, Scott E Boesch, Ian Haken, Pankaj Sinha, Ralph A Wheeler, Angela K WilsonAbstract:Scale factors for (a) low (<1000 cm−1) and high harmonic vibrational frequencies, (b) thermal contributions to enthalpy and entropy, and (c) zero-point vibrational energies have been determined for five hybrid functionals (B3P86, B3PW91, PBE1PBE, BH&HLYP, MPW1K), five pure functionals (BLYP, BPW91, PBEPBE, HCTH93, and BP86), four hybrid meta functionals (M05, M05-2X, M06, and M06-2X) and one double-hybrid functional (B2GP-PLYP) in combination with the correlation Consistent Basis sets [cc-pVnZ and aug-cc-pVnZ, n = D(2),T(3),Q(4)]. Calculations for vibrational frequencies were carried out on 41 organic molecules and an additional set of 22 small molecules was used for the zero-point vibrational energy scale factors. Before scaling, approximately 25% of the calculated frequencies were within 3% of experimental frequencies. Upon application of the derived scale factors, nearly 90% of the calculated frequencies deviated less than 3% from the experimental frequencies for all of the functionals when the augmented correlation Consistent Basis sets were used. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Kirk A. Peterson - One of the best experts on this subject based on the ideXlab platform.
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Correlation Consistent Basis sets with relativistic effective core potentials : The transition metal elements Y and Hg
2020Co-Authors: Kirk A. PetersonAbstract:Gaussian Basis sets for the elements Y and Hg appropriate for valence electron correlation have been developed using a correlation Consistent prescription with accurate relativistic effective core potentials. The resulting sequences of Basis sets are denoted cc-pVnZ-PP (correlation Consistent polarized relativistic valence n-Q and range in size from n = D-5. In each case systematic convergence towards the complete Basis set limit is clearly observed for both the Hartree-Fock and correlation energies. In the case of Hg, all-electron Basis sets are also reported both with and without the inclusion of scalar relativity via the Douglas-Kroll-Hess Hamiltonian. The accuracy of the resulting Basis sets is demonstrated in benchmark calculations on YC, HgH + , and Hg 2 . Predictions are made for r e and D c for YC and D c for HgH + . In all three cases, the results appear to be the most accurate to date and agree very well with experiment.
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Correlation Consistent Basis sets for actinides. II. The atoms Ac and Np–Lr
Journal of Chemical Physics, 2017Co-Authors: Rulin Feng, Kirk A. PetersonAbstract:New correlation Consistent Basis sets optimized using the all-electron third-order Douglas-Kroll-Hess (DKH3) scalar relativistic Hamiltonian are reported for the actinide elements Ac and Np through Lr. These complete the series of sets reported previously for Th–U [K. A. Peterson, J. Chem. Phys. 142, 074105 (2015); M. Vasiliu et al., J. Phys. Chem. A 119, 11422 (2015)]. The new sets range in size from double- to quadruple-zeta and encompass both those optimized for valence (6s6p5f7s6d) and outer-core electron correlations (valence + 5s5p5d). The final sets have been contracted for both the DKH3 and eXact 2-component (X2C) Hamiltonians, yielding cc-pVnZ-DK3/cc-pVnZ-X2C sets for valence correlation and cc-pwCVnZ-DK3/cc-pwCVnZ-X2C sets for outer-core correlation (n = D, T, Q in each case). In order to test the effectiveness of the new Basis sets, both atomic and molecular benchmark calculations have been carried out. In the first case, the first three atomic ionization potentials (IPs) of all the actinide el...
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correlation Consistent Basis sets for actinides ii the atoms ac and np lr
Journal of Chemical Physics, 2017Co-Authors: Rulin Feng, Kirk A. PetersonAbstract:New correlation Consistent Basis sets optimized using the all-electron third-order Douglas-Kroll-Hess (DKH3) scalar relativistic Hamiltonian are reported for the actinide elements Ac and Np through Lr. These complete the series of sets reported previously for Th–U [K. A. Peterson, J. Chem. Phys. 142, 074105 (2015); M. Vasiliu et al., J. Phys. Chem. A 119, 11422 (2015)]. The new sets range in size from double- to quadruple-zeta and encompass both those optimized for valence (6s6p5f7s6d) and outer-core electron correlations (valence + 5s5p5d). The final sets have been contracted for both the DKH3 and eXact 2-component (X2C) Hamiltonians, yielding cc-pVnZ-DK3/cc-pVnZ-X2C sets for valence correlation and cc-pwCVnZ-DK3/cc-pwCVnZ-X2C sets for outer-core correlation (n = D, T, Q in each case). In order to test the effectiveness of the new Basis sets, both atomic and molecular benchmark calculations have been carried out. In the first case, the first three atomic ionization potentials (IPs) of all the actinide el...
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Correlation Consistent Basis sets for lanthanides: The atoms La–Lu
Journal of Chemical Physics, 2016Co-Authors: Qing Lu, Kirk A. PetersonAbstract:Using the 3rd-order Douglas-Kroll-Hess (DKH3) Hamiltonian, all-electron correlation Consistent Basis sets of double-, triple-, and quadruple-zeta quality have been developed for the lanthanide elements La through Lu. Basis sets designed for the recovery of valence correlation (defined here as 4f5s5p5d6s), cc-pVnZ-DK3, and outer-core correlation (valence + 4s4p4d), cc-pwCVnZ-DK3, are reported (n = D, T, and Q). Systematic convergence of both Hartree-Fock and correlation energies towards their respective complete Basis set (CBS) limits are observed. Benchmark calculations of the first three ionization potentials (IPs) of La through Lu are reported at the DKH3 coupled cluster singles and doubles with perturbative triples, CCSD(T), level of theory, including effects of correlation down through the 4s electrons. Spin-orbit coupling is treated at the 2-component HF level. After extrapolation to the CBS limit, the average errors with respect to experiment were just 0.52, 1.14, and 4.24 kcal/mol for the 1st, 2nd,...
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correlation Consistent Basis sets for lanthanides the atoms la lu
Journal of Chemical Physics, 2016Co-Authors: Qing Lu, Kirk A. PetersonAbstract:Using the 3rd-order Douglas-Kroll-Hess (DKH3) Hamiltonian, all-electron correlation Consistent Basis sets of double-, triple-, and quadruple-zeta quality have been developed for the lanthanide elements La through Lu. Basis sets designed for the recovery of valence correlation (defined here as 4f5s5p5d6s), cc-pVnZ-DK3, and outer-core correlation (valence + 4s4p4d), cc-pwCVnZ-DK3, are reported (n = D, T, and Q). Systematic convergence of both Hartree-Fock and correlation energies towards their respective complete Basis set (CBS) limits are observed. Benchmark calculations of the first three ionization potentials (IPs) of La through Lu are reported at the DKH3 coupled cluster singles and doubles with perturbative triples, CCSD(T), level of theory, including effects of correlation down through the 4s electrons. Spin-orbit coupling is treated at the 2-component HF level. After extrapolation to the CBS limit, the average errors with respect to experiment were just 0.52, 1.14, and 4.24 kcal/mol for the 1st, 2nd, and 3rd IPs, respectively, compared to the average experimental uncertainties of 0.03, 1.78, and 2.65 kcal/mol, respectively. The new Basis sets are also used in CCSD(T) benchmark calculations of the equilibrium geometries, atomization energies, and heats of formation for Gd2, GdF, and GdF3. Except for the equilibrium geometry and harmonic frequency of GdF, which are accurately known from experiment, all other calculated quantities represent significant improvements compared to the existing experimental quantities. With estimated uncertainties of about ±3 kcal/mol, the 0 K atomization energies (298 K heats of formation) are calculated to be (all in kcal/mol): 33.2 (160.1) for Gd2, 151.7 (-36.6) for GdF, and 447.1 (-295.2) for GdF3.
Frank Jensen - One of the best experts on this subject based on the ideXlab platform.
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development of polarization Consistent Basis sets for spin spin coupling constant calculations for the atoms li be na and mg
Journal of Chemical Physics, 2018Co-Authors: Patrick Alexander Aggelund, Stephan P A Sauer, Frank JensenAbstract:The pcJ-n Basis set, optimized for spin-spin coupling constant calculations using density functional theory methods, are expanded to also include the s-block elements Li, Be, Na, and Mg, by studyin...
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unifying general and segmented contracted Basis sets segmented polarization Consistent Basis sets
Journal of Chemical Theory and Computation, 2014Co-Authors: Frank JensenAbstract:We propose a method, denoted P-orthogonalization, for converting a general contracted Basis set to a computationally more efficient segmented contracted Basis set, while inheriting the full accuracy of the general contracted Basis set. The procedure can be used for any general contracted Basis set to remove the redundancies between general contracted functions in terms of primitive functions. The P-orthogonalization procedure is used to construct a segmented contracted version of the polarization Consistent Basis sets, which are optimized for density functional theory calculations. Benchmark calculations show that the new pcs-n Basis sets provide uniform error control of the Basis set incompleteness for molecular systems composed of atoms from the first three rows in the periodic table (H–Kr) and for different exchange-correlation functionals. The Basis set errors at a given zeta quality level are lower than other existing Basis sets, and the pcs-n Basis sets are furthermore shown to be among the computat...
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polarization Consistent Basis sets viii the transition metals sc zn
Journal of Chemical Physics, 2013Co-Authors: Frank JensenAbstract:Polarization Consistent Basis sets, optimized for density functional calculations, are proposed for the transition metals Sc-Zn. The Basis set composition in terms of number of primitive functions and the contraction is defined based on energetic analyses of atoms and molecules along the lines used in previous work and on the performance for molecular systems. The performance for atomization energies and dipole moments is compared to other widely used Basis sets, and it is shown that the new Basis sets allow a systematic reduction of Basis set errors and, in general, have Basis set errors lower than or at par with existing ones.
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polarization Consistent Basis sets vii the elements k ca ga ge as se br and kr
Journal of Chemical Physics, 2012Co-Authors: Frank JensenAbstract:Polarization Consistent Basis sets, optimized for density functional calculations, are proposed for the elements K, Ca, Ga, Ge, As, Se, Br, and Kr. The Basis set composition in terms of number of primitive functions and the contraction is defined based on energetic analyses of atoms and molecules along the lines used in previous work and on the performance for molecular systems. The performance for atomization energies and dipole moments is compared to other widely used Basis sets, and it is shown that the new Basis sets allow a systematic reduction of Basis set errors and in general perform better than existing ones.
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Optimized Basis Sets for Calculating Spin‐Spin Coupling Constants
AIP Conference Proceedings, 2008Co-Authors: Udo Benedikt, Alexander A. Auer, Frank JensenAbstract:We propose a series of Basis sets for systematically reducing the Basis set error for calculating nuclear spin‐spin coupling constants. At the density functional level, the Basis sets are derived from the previously proposed polarization Consistent Basis sets by augmentation with tight s‐, p‐, d‐ and f‐functions. The optimum exponents for the tight functions can be derived by a variational procedure, and the optimum exponents are sufficiently regular that a standard set of tight functions can be derived. Preliminary results at the coupled cluster level suggest that a similar sequence of optimum Basis sets can be derived from the correlation Consistent Basis sets by augmentation with tight functions.
Thom H Dunning - One of the best experts on this subject based on the ideXlab platform.
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so2 revisited impact of tight d augmented correlation Consistent Basis sets on structure and energetics
Journal of Chemical Physics, 2003Co-Authors: Angela K Wilson, Thom H DunningAbstract:The total energies, atomization energies, molecular structures, and harmonic vibrational frequencies of SO2 have been determined using the newly revised correlation Consistent Basis sets, cc-pV(n+d)Z, with n=2–5. The impact of the additional tight d functions on the energies, structures, and frequencies as well as the convergence of these quantities to the complete Basis set (CBS) limit is examined. Overall, the revised sets result in faster convergence to the CBS limit. The effect of the additional tight d function is particularly dramatic for the lower level, double zeta and triple zeta, Basis sets.
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accurate correlation Consistent Basis sets for molecular core valence correlation effects the second row atoms al ar and the first row atoms b ne revisited
Journal of Chemical Physics, 2002Co-Authors: Kirk A. Peterson, Thom H DunningAbstract:Correlation Consistent Basis sets for accurately describing core–core and core–valence correlation effects in atoms and molecules have been developed for the second row atoms Al–Ar. Two different optimization strategies were investigated, which led to two families of core–valence Basis sets when the optimized functions were added to the standard correlation Consistent Basis sets (cc-pVnZ). In the first case, the exponents of the augmenting primitive Gaussian functions were optimized with respect to the difference between all-electron and valence–electron correlated calculations, i.e., for the core–core plus core–valence correlation energy. This yielded the cc-pCVnZ family of Basis sets, which are analogous to the sets developed previously for the first row atoms [D. E. Woon and T. H. Dunning, Jr., J. Chem. Phys. 103, 4572 (1995)]. Although the cc-pCVnZ sets exhibit systematic convergence to the all-electron correlation energy at the complete Basis set limit, the intershell (core–valence) correlation energ...
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Accurate correlation Consistent Basis sets for molecular core–valence correlation effects: The second row atoms Al–Ar, and the first row atoms B–Ne revisited
Journal of Chemical Physics, 2002Co-Authors: Kirk A. Peterson, Thom H DunningAbstract:Correlation Consistent Basis sets for accurately describing core–core and core–valence correlation effects in atoms and molecules have been developed for the second row atoms Al–Ar. Two different optimization strategies were investigated, which led to two families of core–valence Basis sets when the optimized functions were added to the standard correlation Consistent Basis sets (cc-pVnZ). In the first case, the exponents of the augmenting primitive Gaussian functions were optimized with respect to the difference between all-electron and valence–electron correlated calculations, i.e., for the core–core plus core–valence correlation energy. This yielded the cc-pCVnZ family of Basis sets, which are analogous to the sets developed previously for the first row atoms [D. E. Woon and T. H. Dunning, Jr., J. Chem. Phys. 103, 4572 (1995)]. Although the cc-pCVnZ sets exhibit systematic convergence to the all-electron correlation energy at the complete Basis set limit, the intershell (core–valence) correlation energ...
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the effect of Basis set superposition error bsse on the convergence of molecular properties calculated with the correlation Consistent Basis sets
Advances in Quantum Chemistry, 1998Co-Authors: Tanja Van Mourik, Kirk A. Peterson, Angela K Wilson, David E Woon, Thom H DunningAbstract:It is shown that, in many cases, the convergence behavior of molecular properties computed with the correlation Consistent Basis sets (both standard and augmented sets) is significantly improved if Basis set superposition error (BSSE) is taken into account. The effects are most pronounced for pure van der Waals systems like the helium or argon dimers. For these systems the uncorrected D e , r e , and ω e behave very irregularly with increasing Basis set size, with the convergence behavior being dramatically improved by use of the counterpoise procedure. Even for strongly bound diatomics like N 2 , HF, and HCl, the counterpoise correction often significantly improves the convergence behavior of r e and ω e . Similar behavior is observed in the weakly bound molecular complexes, ArHF, HCO − , and (HF) 2 , as well as for the more strongly bound HCO molecule. For HCO − , because of the pronounced lengthening of the CO bond upon molecular formation, the deformation energy must also be taken into account.
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gaussian Basis sets for use in correlated molecular calculations vi sextuple zeta correlation Consistent Basis sets for boron through neon
Journal of Molecular Structure-theochem, 1996Co-Authors: Angela K Wilson, Tanja Van Mourik, Thom H DunningAbstract:Abstract The family of correlation Consistent polarized valence Basis sets (cc-pVXZ) has been extended to include sextuple zeta sets (cc-pV6Z) for the atoms boron through neon. Potential energy functions have been calculated with these sets for the electronic ground states of N2 and HF using a number of correlated wave functions: MP2, MP3, MP4, CCSD, CCSD(T) and CAS+1+2. Spectroscopic constants have been calculated for each level of theory and have been compared with experiment. Combining these results with those of prior studies, complete Basis set limits have been estimated for Ee, De and re. It is found that the cc-pV6Z Basis sets yield dissociation energies that are within 0.6–0.8 kcal mol−1 (N2) and 0.1 kcal mol−1 (HF) of the estimated CBS limits. Adding core-core and core-valence contributions to the CCSD(T) CBS limits yields De's that are within 0.1 kcal mol−1 of the experimental values.
Christof Hattig - One of the best experts on this subject based on the ideXlab platform.
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vibrational frequency scaling factors for correlation Consistent Basis sets and the methods cc2 and mp2 and their spin scaled scs and sos variants
Journal of Chemical Physics, 2014Co-Authors: Daniel H Friese, Lisa Tork, Christof HattigAbstract:We present scaling factors for vibrational frequencies calculated within the harmonic approximation and the correlated wave-function methods coupled cluster singles and doubles model (CC2) and Moller-Plesset perturbation theory (MP2) with and without a spin-component scaling (SCS or spin-opposite scaling (SOS)). Frequency scaling factors and the remaining deviations from the reference data are evaluated for several non-augmented Basis sets of the cc-pVXZ family of generally contracted correlation-Consistent Basis sets as well as for the segmented contracted TZVPP Basis. We find that the SCS and SOS variants of CC2 and MP2 lead to a slightly better accuracy for the scaled vibrational frequencies. The determined frequency scaling factors can also be used for vibrational frequencies calculated for excited states through response theory with CC2 and the algebraic diagrammatic construction through second order and their spin-component scaled variants.
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efficient use of the correlation Consistent Basis sets in resolution of the identity mp2 calculations
Journal of Chemical Physics, 2002Co-Authors: Florian Weigend, Andreas Kohn, Christof HattigAbstract:The convergence of the second-order Moller–Plesset perturbation theory (MP2) correlation energy with the cardinal number X is investigated for the correlation Consistent Basis-set series cc-pVXZ and cc-pV(X+d)Z. For the aug-cc-pVXZ and aug-cc-pV(X+d)Z series the convergence of the MP2 correlation contribution to the dipole moment is studied. It is found that, when d-shell electrons cannot be frozen, the cc-pVXZ and aug-cc-pVXZ Basis sets converge much slower for third-row elements then they do for first- and second-row elements. Based on the results of these studies criteria are deduced for the accuracy of auxiliary Basis sets used in the resolution of the identity (RI) approximation for electron repulsion integrals. Optimized auxiliary Basis sets for RI-MP2 calculations fulfilling these criteria are reported for the sets cc-pVXZ, cc-pV(X+d)Z, aug-cc-pVXZ, and aug-cc-pV(X+d)Z with X=D, T, and Q. For all Basis sets the RI error in the MP2 correlation energy is more than two orders of magnitude smaller than...