节面是原子、分子轨道的一个重要的特征。原子轨道的径向分布函数有n-l-1个节面,节面形状为球形。角度分布函数有l个节面,节面形状为平面(或锥形)。σ成键分子轨道、π成键分子轨道和δ成键分子轨道的特征是过键轴的节面个数分别有0个、1个和2个。σ*反键分子轨道、π*反键分子轨道和δ*反键分子轨道的特征是它们除过键轴的节面外还有1个垂直于键轴的节面。 The nodal plane is an important feature of atomic orbitals. The radial distribution function of atomic orbitals has n-1-n sections and the nodal shape is spherical. The angular distribution function has 1 nodal plane and the nodal plane is flat (or tapered). The characteristics of the σ-bonded molecular orbital, the π-bonded molecular orbitals and the δ-bonded molecular orbitals are 0, 1 and 2, respectively. The characteristic of the σ * antibonding molecular orbital, π * antibonding molecular or δ * antibonding molecular orbital is that they have, in addition to the nodal plane of the key shaft, a nodal plane perpendicular to the key shaft.