Spin polarization effect for Co2 molecule

Spin polarization effect for Co2 molecule

The density functional theory (DFT)(b3p86) of Gaussian 03 has beenused to optimize the structure of the Co$_{2}$ molecule, a transitionmetal element molecule. The result shows that the ground state forthe Co$_{2}$ molecule is a 7-multiple state, indicating a spinpolarization effect in the Co$_{2}$ molecule. Meanwhile, we have notfound any spin pollution because the wavefunction of the ground stateis not mingled with wavefunctions of higher-energy states. So for theground state of Co$_{2}$ molecule to be a 7-multiple state is theindicative of spin polarization effect of the Co$_{2}$ molecule, thatis, there exist 6 parallel spin electrons in a Co$_{2}$ molecule. Thenumber of non-conjugated electrons is the greatest. These electronsoccupy different spacial orbitals so that the energy of the Co$_{2}$molecule is minimized. It can be concluded that the effect ofparallel spin in the Co$_{2}$ molecule is larger than the effect ofthe conjugated molecule, which is obviously related to the effect ofelectron d delocalization. In addition, the Murrell--Sorbie potentialfunctions with the parameters for the ground state and the otherstates of the Co$_{2}$ molecule are derived. The dissociation energy$De$ for the ground state of Co$_{2}$ molecule is 4.0489eV,equilibrium bond length $R_{rm e}$ is 0.2061~nm, and vibrationfrequency $omega _e $ is 378.13~cm$^{ - 1}$. Its diatomic moleculeforce constants $f_2$, $f_3$, and $f_4$ are 2.4824~aJ$cdot$nm$^{ -2}$, -7.3451~aJ$cdot$nm$^{ - 3}$, and 11.2222~aJ$cdot$nm$^{ - 4}$respectively(1~aJ=$10^{-18}$~J). The other spectroscopic data forthe ground state of Co$_{2}$ molecule $omega_{e}chi _{e}$,$B_{e}$, and $alpha_{e}$ are 0.7202~cm$^{-1}$, 0.1347~cm$^{-1 }$,and 2.9120$times $ 10$^{-1}$~cm$^{-1}$ respectively. And$omega_{e}chi _{e}$ is the non-syntonic part of frequency,$B_{e}$ is the rotational constant, $alpha_{e}$ is revisedconstant of rotational constant for non-rigid part of Co$_2$molecule.