| S4 | E | S4 | C2 | S4³ | 线性 / 转动linear, rotations | 二次quadratic |
|---|---|---|---|---|---|---|
| A | 1 | 1 | 1 | 1 | Rz | x²+y², z² |
| B | 1 | −1 | 1 | −1 | z | x²−y², xy |
| E | 12 | i0 | −1−2 | −i0 | (x, y), (Rx, Ry) | (xz, yz) |
| ↳ 共轭conj. | 1 | −i | −1 | i |
\(\varepsilon = \exp(2\pi i/4)\)，\(\varepsilon^{*}\) 为其复共轭。合并后每对复共轭不可约表示相加成一个二维实表示（物理上简并）。; \(\varepsilon^{*}\) is its complex conjugate. Merging adds each conjugate pair into one two-dimensional real representation (physically degenerate).
| 阶 hOrder h | 4 |
|---|---|
| 类数Classes | 4 |
| 所属族Family | Sn |
| 代表分子Examples | 四苯基甲烷（某些构象）, 1,3,5,7-四甲基环辛四烯tetraphenylmethane (some conformers), 1,3,5,7-tetramethylcyclooctatetraene |
约化可约表示Reduce a representation
输入可约表示在各类上的特征标，按约化公式 \(n_i = \frac{1}{h}\sum_R g_R\,\chi(R)\,\chi_i(R)^{*}\) 求出各不可约表示出现的次数。
Enter the characters of a reducible representation; the reduction formula gives how many times each irreducible representation occurs.