请问专家，我在用octopus5计算腺嘌呤和胸腺嘧啶的时候，计算出来的homo和lumo轨道随时间变化不呈现周期性（正常应该是有周期震荡的），我觉得可能是基组的问题。请问在计算时应该如何选择正确的基组泛函呢？这是我选择的基组XCFunctional = gga_x_b88 + gga_c_lyp，以及其他的参数BoxShape = minimum Radius = 7.5589 Spacing = 0.472 ConvRelDens = 1e-8 SpinComponents = spin_polarized ExtraStates = 6 MoveIons = yes TDDynamics = ehrenfest dt = 0.01 T = 4500 TDTimeStep = dt TDMaximumIter = T/TDTimeStep TDPropagator = aetrs ExperimentalFeautures = yes TDOutput = multipoles + energy + geometry + temperature + eigenvalues OutputInterval = 1000 Output = density + geometry OutputHow = xcrysden + cube