Local hybrid functionals augmented by a strong-correlation model

2021 ◽  
Vol 155 (14) ◽  
pp. 144101
Author(s):  
Artur Wodyński ◽  
Alexei V. Arbuznikov ◽  
Martin Kaupp
Keyword(s):  
Strong Correlation ◽  
Correlation Model ◽  
Hybrid Functionals

scholarly journals Optimization of a Range-Separated UW12 Hybrid Functional

2021 ◽  
Author(s):  
Zack Williams ◽  
Frederick Manby
Keyword(s):  
Power Series ◽  
Density Functional ◽  
Power Series Expansion ◽  
Correlation Model ◽  
Hybrid Functional ◽  
Main Group Chemistry ◽  
Self Consistent ◽  
Hybrid Functionals ◽  
Survival Of The Fittest ◽  
Hybrid Density Functional

In a previous paper we presented a new hybrid functional B-LYP-osUW12-D3(BJ) containing the Unsöld-w12 (UW12) hybrid correlation model. In this paper we present a new 15-parameter range-separated hybrid density functional using a power series expansion together with UW12 correlation. This functional is optimised using the survival of the fittest strategy developed for the ωB97X-V functional, fitted to data from the Main Group Chemistry Database (MGCDB84). In addition we optimize a standard hybrid and double hybrid using the same method. We show that our fully self-consistent UW12 hybrid functional WM21-D3(BJ) outperforms both of these functionals and other range-separated hybrid functionals.

Effect of temperature on DNA condensation at single molecule level

2017 ◽  
Vol 31 (13) ◽  
pp. 1750147 ◽  
Author(s):  
Min Zhang ◽  
Lingyun Gu ◽  
Yangtao Fan ◽  
Yanhui Liu ◽  
Xun Zhou
Keyword(s):  
Temperature Effect ◽  
Single Molecule ◽  
Strong Correlation ◽  
Persistence Length ◽  
Dna Condensation ◽  
Effect Of Temperature ◽  
Correlation Model ◽  
Single Molecule Level ◽  
Dna Conformations ◽  
Increasing Temperature

DNA condensation by multivalent cations has been extensively studied using single molecule experiment methods. To detect temperature effect on DNA condensation at the single molecule level, a strong correlation model was developed to investigate the behavior of DNA with self-interactions under constant tension. The simulation results are in line with the single molecule experiment that the kinetics of DNA condensation take on discontinuous and stepwise manner regardless of the toroid or rod-like conformation. By incorporating the temperature dependence of DNA persistence length into the strong correlation model, the temperature effect on DNA condensation is identified. The results indicate that condensed DNA conformations at single molecule level become more compact with increasing temperature.

Cultural and Linguistic Adaptation of the Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V) Into Hindi

2020 ◽  
Vol 63 (12) ◽  
pp. 3974-3981
Author(s):  
Ashwini Joshi ◽  
Isha Baheti ◽  
Vrushali Angadi
Keyword(s):  
Strong Correlation ◽  
Concurrent Validity ◽  
Interrater Reliability ◽  
Voice Quality ◽  
Weak Correlation ◽  
Voice Assessment ◽  
Perceptual Evaluation ◽  
Severity Grade ◽  
Normal Voice ◽  
Group A

Aim The purpose of this study was to develop and assess the reliability of a Hindi version of the Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V). Reliability was assessed by comparing Hindi CAPE-V ratings with English CAPE-V ratings and by the Grade, Roughness, Breathiness, Asthenia and Strain (GRBAS) scale. Method Hindi sentences were created to match the phonemic load of the corresponding English CAPE-V sentences. The Hindi sentences were adapted for linguistic content. The original English and adapted Hindi CAPE-V and GRBAS were completed for 33 bilingual individuals with normal voice quality. Additionally, the Hindi CAPE-V and GRBAS were completed for 13 Hindi speakers with disordered voice quality. The agreement of CAPE-V ratings was assessed between language versions, GRBAS ratings, and two rater pairs (three raters in total). Pearson product–moment correlation was completed for all comparisons. Results A strong correlation ( r > .8, p < .01) was found between the Hindi CAPE-V scores and the English CAPE-V scores for most variables in normal voice participants. A weak correlation was found for the variable of strain ( r < .2, p = .400) in the normative group. A strong correlation ( r > .6, p < .01) was found between the overall severity/grade, roughness, and breathiness scores in the GRBAS scale and the CAPE-V scale in normal and disordered voice samples. Significant interrater reliability ( r > .75) was present in overall severity and breathiness. Conclusions The Hindi version of the CAPE-V demonstrates good interrater reliability and concurrent validity with the English CAPE-V and the GRBAS. The Hindi CAPE-V can be used for the auditory-perceptual voice assessment of Hindi speakers.

PENGARUH KUALITAS PELAYANAN DAN PROMOSI TERHADAP PERLUASAN PANGSA PASAR PRODUK DANA TALANGAN HAJI DI BANK SYARIAH MANDIRI KCP UJUNGBERUNG DAN KCP RANCAEKEK BANDUNG

2018 ◽  
Vol 2 (1) ◽  
pp. 1-15
Author(s):  
Intan Nurrachmi
Keyword(s):  
Quality Of Service ◽  
Service Quality ◽  
Market Share ◽  
Significant Influence ◽  
Strong Correlation ◽  
T Test ◽  
Market Expansion ◽  
Difference Constraints ◽  
Branch Office

This study departs from the hajj bailout financing facility which is a booming product because of the customer's interest, but in this case there is a difference in the target achievement between Bank Syariah Mandiri (BSM) Ujungberung KCP which is less successful in improving the hajj bailout products while the Rancaekek KCP is very superior in one consolidation Ahmad Yani Branch Office Bandung. This is what is interesting for researchers to carry out this research, the difference constraints include service quality and promotion factors. This phenomenon raises problems that must be examined, namely how the influence of service quality and promotion of market share expansion products hajj bailouts at Bank Syariah Mandiri KCP Ujungberung and KCP Rancaekek Bandung. This study aims academically to contribute in the study of Islamic economics in worksheets, especially the quality of service and promotion of market share expansion and practically expected to be able to provide input to all employees of BSM KCP Ujungberung regarding the quality of service and promotion of market expansion of bailout products. Hajj that has been successfully carried out by BSM KCP Rancaekek.The conclusion of this study is that there is a significant influence of service quality on the expansion of market share by 53.3% with a strong correlation of 0.730 and through t test, where t counts at 8.245 (> t table), then H_0 is rejected and H_i is accepted. Furthermore, there is a significant influence of promotion on the expansion of market share by 30.3% with a moderate / sufficient correlation of 0.550 through t test, where t counts is 4.219 (> t table), then H_ (0) is rejected and H_i is accepted. Then there is a significant influence of service quality and promotion simultaneously to the expansion of market share by 60.6% and a strong correlation of 0.784 and through Test F, where F count is 67.023 (> F table), then 〖H〗 _ ( 0) rejected and H_i accepted.

Strong Correlation between the Expression of CHEK1 and Clinicopathological Features of Patients with Multiple Myeloma

2020 ◽  
Vol 30 (4) ◽  
pp. 349-357
Author(s):  
Xiao-Ping Liu ◽  
Qiao-Huang ◽  
Xiao-Hong Yin ◽  
Xiang-Yu Meng ◽  
Yue Cao ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Strong Correlation ◽  
Clinicopathological Features

Evaluating Transition Metal Barrier Heights with the Latest DFT Exchange–Correlation Functionals – the MOBH35 Benchmark Dataset

2019 ◽  
Author(s):  
Mark Iron ◽  
Trevor Janes
Keyword(s):  
Transition Metal ◽  
Density Functional ◽  
Computational Cost ◽  
Basis Set ◽  
Functional Theory ◽  
Exchange Correlation ◽  
Barrier Heights ◽  
Complete Basis Set ◽  
Complete Basis Set Limit ◽  
Hybrid Functionals

A new database of transition metal reaction barrier heights – MOBH35 – is presented. Benchmark energies (forward and reverse barriers and reaction energy) are calculated using DLPNO-CCSD(T) extrapolated to the complete basis set limit using a Weizmann1-like scheme. Using these benchmark energies, the performance of a wide selection of density functional theory (DFT) exchange–correlation functionals, including the latest from the Truhlar and Head-Gordon groups, is evaluated. It was found, using the def2-TZVPP basis set, that the ωB97M-V (MAD 1.8 kcal/mol), ωB97X-V (MAD 2.1 kcal/mol) and SCAN0 (MAD 2.1 kcal/mol) hybrid functionals are recommended. The double-hybrid functionals PWPB95 (MAD 1.6 kcal/mol) and B2K-PLYP (MAD 1.8 kcal/mol) did perform slightly better but this has to be balanced by their increased computational cost.

Minimally Empirical Double Hybrid Functionals Trained Against the GMTKN55 Database: revDSD-PBEP86-D4, revDOD-PBE-D4, and DOD-SCAN-D4

2019 ◽  
Author(s):  
Golokesh Santra ◽  
Nitai Sylvetsky ◽  
Gershom Martin
Keyword(s):  
Substantial Improvement ◽  
Viable Alternative ◽  
Mean Absolute Deviation ◽  
Dispersion Correction ◽  
Training Set ◽  
Weighted Mean ◽  
Absolute Deviation ◽  
Hybrid Functionals ◽  
Scaling Algorithms

We present a family of minimally empirical double-hybrid DFT functionals parametrized against the very large and diverse GMTKN55 benchmark. The very recently proposed wB97M(2) empirical double hybrid (with 16 empirical parameters) has the lowest WTMAD2 (weighted mean absolute deviation over GMTKN55) ever reported at 2.19 kcal/mol. However, our xrevDSD-PBEP86-D4 functional reaches a statistically equivalent WTMAD2=2.22 kcal/mol, using just a handful of empirical parameters, and the xrevDOD-PBEP86-D4 functional reaches 2.25 kcal/mol with just opposite-spin MP2 correlation, making it amenable to reduced-scaling algorithms. In general, the D4 empirical dispersion correction is clearly superior to D3BJ. If one eschews dispersion corrections of any kind, noDispSD-SCAN offers a viable alternative. Parametrization over the entire GMTKN55 dataset yields substantial improvement over the small training set previously employed in the DSD papers.

Minimally Empirical Double Hybrid Functionals Trained Against the GMTKN55 Database: revDSD-PBEP86-D4, revDOD-PBE-D4, and DOD-SCAN-D4

2019 ◽  
Author(s):  
Golokesh Santra ◽  
Nitai Sylvetsky ◽  
Gershom Martin
Keyword(s):  
Substantial Improvement ◽  
Viable Alternative ◽  
Mean Absolute Deviation ◽  
Dispersion Correction ◽  
Training Set ◽  
Weighted Mean ◽  
Absolute Deviation ◽  
Hybrid Functionals ◽  
Scaling Algorithms

We present a family of minimally empirical double-hybrid DFT functionals parametrized against the very large and diverse GMTKN55 benchmark. The very recently proposed wB97M(2) empirical double hybrid (with 16 empirical parameters) has the lowest WTMAD2 (weighted mean absolute deviation over GMTKN55) ever reported at 2.19 kcal/mol. However, our xrevDSD-PBEP86-D4 functional reaches a statistically equivalent WTMAD2=2.22 kcal/mol, using just a handful of empirical parameters, and the xrevDOD-PBEP86-D4 functional reaches 2.25 kcal/mol with just opposite-spin MP2 correlation, making it amenable to reduced-scaling algorithms. In general, the D4 empirical dispersion correction is clearly superior to D3BJ. If one eschews dispersion corrections of any kind, noDispSD-SCAN offers a viable alternative. Parametrization over the entire GMTKN55 dataset yields substantial improvement over the small training set previously employed in the DSD papers.

Electronic or steric effects: Detailed DFT investigations of titanium amino based Kaminsky type olefin catalysts

2018 ◽  
Author(s):  
Jörg Saßmannshausen
Keyword(s):  
Density Functional Theory ◽  
Strong Correlation ◽  
Density Functional ◽  
Steric Effects ◽  
Aryl Group ◽  
Functional Theory

We report detailed Density Functional Theory (DFT) investigations of a series of structurally similar titanium (IV) chelating σ-aryl catalysts. Particular attention was paid to the electronic charges of the Ti, C ipso of the substituted aryl group and the benzylic CH<sub>2</sub> and C<i><sub>ipso</sub></i> atoms. The Bader and NBO derived charges were compared with the recently reported polymerisation results by Chan. We found a strong correlation between the relative energies of one of the computed isomers and the activity of the catalyst. Neither NBO nor Bader charges could be convincingly correlated to the observed activity.

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