The theory of ground state and excited state energies calculations of multielectron quantum dot with hydrogenic impurity within the effective mass approximation has been given. Results show that ground and excited state energies decrease with dot radius. In the present paper, calculation has been carried out for two electron quantum dot. The effect of magnetic field on first excited state for d...

Recent measurements of transmission versus fluence for a methanol-solvated asymmetric pentaazadentate porphyrin-like (APPC) cadmium complex, @(C6H4 – APPC)Cd]Cl, showed the limitations of current energy-level models in predicting the transmission behavior of organic reverse saturable absorbers at fluences greater than 1 J/cm2. A new model has been developed that incorporates higher-order triple...

We present a new method for the computation of electronic excited states of molecular systems. This method is based upon a recent theoretical definition of multiconfiguration excited states (due to one of us, see M. Lewin, Solutions of the Multiconfiguration Equations in Quantum Chemistry, Arch. Rat. Mech. Anal. 171 (2004) 83-114). Our algorithm, dedicated to the computation of the first excite...

Fluorescence and phosphorescence are photon emission processes that occur during molecular relaxation from electronic excited states. These photonic processes involve transitions between electronic and vibrational states of polyatomic fluorescent molecules (fluorophores). The Jablonski diagram (Figure 1) offers a convenient representation of the excited state structure and the relevant transiti...

The electronic absorption and emission spectra of the [n]cycloparaphenylenes with n = 6,7,...,11 ([n]CP) have been studied at the time-dependent density functional theory level. The calculations show that the optical gap increases with increasing size of the ring due to reduced ring strain in the larger carbon nanohoops, whereas the energy of the first bright state follows the opposite trend fo...

In local effective potential energy theories such as the Hohenberg-Kohn-Sham density functional theory (HKS-DFT) and quantal density functional theory (Q-DFT), electronic systems in their ground or excited states are mapped to model systems of noninteracting fermions with equivalent density. From these models, the equivalent total energy and ionization potential are also obtained. This paper co...

The photochemistry of TiO2 has been studied intensively since it was discovered that TiO2 can act as a photocatalyst. Nevertheless, it has proven difficult to establish the detailed charge-transfer processes involved, partly because the excited states involved are difficult to study. Here we present evidence of the existence of hydroxyl-induced excited states in the conduction band region. Usin...

Over the past few years, the detection of single N-V centers in diamond has attracted much interest, since it is expected to lead to innovative applications in various domains of quantum information. The N-V center in diamond is a defect consisting of a substitutional nitrogen atom adjacent to a carbon-atom vacancy. The optical transition between the A ground state and the E excited state has a...

The ground state, singlet! singlet and singlet! triplet vertical excited states of styrene have been studied by using the symmetry adapted cluster-configuration interaction (SAC-CI) method with aug-cc-pVDZ basis sets supplemented with molecule-centered Rydberg functions. The characteristic structures of the bands observed in the vacuum ultraviolet (VUV) and electron energy loss (EEL) spectra ha...

In this paper a resonant tunnelling quantum well infrared photodetector (RT-QWIP) is discussed. Each period of this photodetector structure comprises of a resonant tunnelling structure (AlAs/AlGaAs/AlAs) nearby a quantum well (AlGaAs/GaAs). In this photodetector, photocurrent is produced when an electron makes a transition from the ground state of the well to an excited state which is coupled t...