DAE-HWAN AHN

Dr. DAE-HWAN AHN

orcid

Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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30 September 2024 in Analytical Chemistry
Verified
Journal Article
Closed access
JSJian Shen
Jian Shen
KRKanagaraj Rajalakshmi
Kanagaraj Rajalakshmi
Selvaraj MuthusamySelvaraj Muthusamy
Selvaraj Muthusamy
DADAE-HWAN AHN
DAE-HWAN AHN
JSJong-Won Song
Jong-Won Song
DZDongwei Zhu
Dongwei Zhu

3 August 2015 in Physical Review C
Verified
Journal Article
Closed access
PDF file
RLR. Lozeva
R. Lozeva
AOA. Odahara
A. Odahara
CMC.-B. Moon
C.-B. Moon
SNS. Nishimura
S. Nishimura
PDP. Doornenbal
P. Doornenbal
KTK. Tshoo
K. Tshoo
We report new data on the Sb1366− yrast isomer with T1/2=489(40) ns and πg7/21×νf7/23 configuration, populated in the projectile fission of U238 on a Be9 target. The analysis confirms the lifetime, providing a good accuracy measurement. In addition, the decay of the isomer to the ground state is newly suggested. Our result for the isomeric decay scheme is in a good agreement with shell-model calculations.



18 September 2024 in Molecules
Verified
Journal Article
Open access
PDF file
HBHan-Seok Bae
Han-Seok Bae
DADAE-HWAN AHN
DAE-HWAN AHN
JSJong-Won Song
Jong-Won Song
We performed intra- and intermolecular charge transfer (CT) excitation energy calculations of (a) conjugated carbon chain [H2N–(CH=CH)n–X] and (b) its equidistant H2NH∙∙∙HX (n = 2~8) with various electron acceptors (X = NH2, OH, Cl, CHO, CN, and NO2) using EOM-CCSD, time-dependent (TD) Hartree–Fock (HF) and various density functional theory (DFT) functionals, such as BLYP, B3LYP, long-range corrected (LC) DFT, and LC-DFT with an optimally tuned (OT) range separation parameter (µ) using Koopman’s theorem to investigate the effect of the electron-withdrawing (or -donating) strength of end-capped functional group (X) and CT distance (R) on intra- and intermolecular CT excitation energies. As the electron-withdrawing strength of X increases, both intra- and intermolecular CT excitation energies tend to decrease, since energy gaps between orbitals corresponding to CT excitations (e.g., HOMO and LUMO) decrease. However, the effect of the electron-withdrawing group on intramolecular CT excitation energy is negligible (at most 0.5 eV). OT-LC-DFT shows accurate intermolecular CT excitation energy, but worse results in intramolecular CT excitation energy than LC-DFT with the default µ value (0.47). Therefore, we conclude that the optimal tuning method is not effective in predicting intramolecular CT excitation energy. While intermolecular CT excitation energy has excitonic binding energy with asymptotic behavior to CT distance that is not affected by the choice of range separation parameter, intramolecular CT excitation energy is affected by orbital relaxation energy, which strongly depends on the choice of range separation parameter, which makes the OT method of range separation parameter ineffective in predicting intramolecular CT excitation energy as well as local excitation with high accuracy.