Phosphorescent materials are one of the focuses in OLED development. By calculating the phosphorescent emission wavelength of organic dyes, the potential of compounds as phosphorescent materials can be predicted.

Figure 1. Excited state and fluorescence, phosphorescence.

As shown in Figure 1, the compound releases energy in the form of photons when de-excited from the excited triplet state T1 to the ground state singlet state S0. Assuming that this energy is all converted into photons, the wavelength of the photon corresponds to the emitted phosphorescence wavelength . In this process, T1 and S0 have exactly the same conformation. First, calculate the conformation and energy of T1, and then use the T1 conformation to calculate the S0 energy. The energy difference between the two is the wavelength. T1 is a triplet state, and its energy can be calculated using TD-DFT (td=triplet) or DFT (set the spin multiplicity to 3). Calculating the excited state in TD-DFT will inevitably calculate the energy of the ground state S0. Therefore, by optimizing the structure by TDDFT, the energy difference between the excited state and the ground state (the emitted phosphorescence wavelength) is directly obtained. With the latter calculation, it is necessary to calculate S0 separately with a single point energy to obtain the energy difference.

Overall solutions

Our services

CD ComputaBio' phosphorescence spectrum prediction service can reduce the cost of later experimental screening. Phosphorescence spectrum prediction service is a personalized and customized innovative scientific research service. Before determining the corresponding analysis plan and price, each project needs to be evaluated. If you want to know more about service prices or technical details, please feel free to contact us.