In the single-configuration approximation, fine-structure parameters are calculated semiempirically in the intermediate coupling scheme for the configurations 2p⁵nf(n = 4-6) of Nel, 3p⁵nf(n = 4-7) of ArI, and 4p⁵4f of KrI. With the fine-structure parameters obtained, the coefficients of expansion of the wave functions in basis functions of the LS-coupling scheme and the gyromagnetic ratios are calculated. To the authors' knowledge, analogous data are absent in the literature. The correctness of the fine-structure parameters obtained is confirmed by values of the fine-splitting constant, which is well known for other configurations of rare-gas atoms with an almost filled p shell.