$$P_i = \epsilon_0 \chi_ij^(1) E_j + \epsilon_0 \chi_ijk^(2) E_j E_k + \epsilon_0 \chi_ijkl^(3) E_j E_k E_l + ...$$
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The software calculated the angle: 168.6 degrees. $$P_i = \epsilon_0 \chi_ij^(1) E_j + \epsilon_0 \chi_ijk^(2)