On the controversial nature of the 1 B-1(u) and 2 B-1(u) states of trans-stilbene: The n-electron valence state perturbation theory approach(385 views) Angeli C, Improta R, Santoro F
Keywords: Energy State, Experimental Observations, Experimental Values, First Excited State, Highest Occupied Molecular Orbitals, Lowest Un-Occupied Molecular Orbitals, Multi References, Oscillator Strengths, Perturbation Theories, Perturbation Theory Methods, Singlet State, Time-Dependent Density Functional Theories, Trans Stilbenes, Valence State, Vertical Excitation Energies, Molecular Modeling, Probability Density Function, Semiconductor Quantum Dots, Perturbation Techniques, Stilbene Derivative, Article, Chemistry, Electron, Quantum Theory, Stereoisomerism,
Affiliations: *** IBB - CNR ***
Dipartimento di Chimica, Universit̀ di Ferrara, via Borsari 46, I-44100 Ferrara, Italy
Istituto di Biostrutture e Bioimmagini, CNR, via Mezzocannone 16, I-80134 Napoli, Italy
Istituto per i Processi Chimico-Fisici, CNR, Area della Ricerca Del CNR, via Moruzzi 1, I-56124 Pisa, Italy
References: Not available.
On the controversial nature of the 1 B-1(u) and 2 B-1(u) states of trans-stilbene: The n-electron valence state perturbation theory approach
The nature of two lowest-energy states of B-u symmetry of trans-stilbene and the accurate calculation of their vertical excitation energy have been the subject of a controversy because time dependent density functional theory (TD-DFT) calculations, in agreement with experimental observations, have questioned the results obtained with multireference perturbation theory (MRPT) in the CASPT2 implementation. This paper aims to solve this controversy. By using a different version of MRPT, the n-electron valence state perturbation theory method, the description provided by TD-DFT is confirmed: the lowest B-u singlet state has a HOMO -> LUMO nature and a large oscillator strength (HOMO refers to highest occupied molecular orbital and LUMO refers to lowest unoccupied molecular orbital), while the second B-u singlet state has a mixed HOMO-1 -> LUMO and HOMO -> LUMO+1 nature, has an oscillator strength almost vanishing, and is located at 0.6-0.7 eV higher than the first excited state. The computed vertical excitation energy to the first state (3.8-4.0 eV) is in good agreement with the experimental value.
On the controversial nature of the 1 B-1(u) and 2 B-1(u) states of trans-stilbene: The n-electron valence state perturbation theory approach
No results.
On the controversial nature of the 1 B-1(u) and 2 B-1(u) states of trans-stilbene: The n-electron valence state perturbation theory approach