Table 3.

Excitation energies in wavenumber units ($\tilde{\nu }$ ) and oscillator strengths (f) calculated using CASSCF‐NEVPT2/aug‐cc‐pVTZ for excitation to states S_n and D_n of the rhodamine cation and radical, respectively. The excitation wavelengths (λ) have been scaled by a factor of 1.3 for better comparison with experiment.

	Rhodamine cation			Rhodamine radical
n	$\tilde{\nu }$ [cm−1]	λ [nm]	f	$\tilde{\nu }$ [cm−1]	λ [nm]	f
1	23 953.2	542.75	1.01954	18 033.8	720.85	0.00013
2	28 954.9	449.02	0.00965	22 509.4	577.59	0.00598
3	34 826.7	373.23	0.00025	23 316.2	557.57	0.00051
4	36 041.4	360.75	0.05518	24 365.7	533.52	0.00162
5	38 191.6	340.34	0.00477	28 023.2	463.84	0.52697
6	42 200.2	308.10	0.01817	31 800.6	408.85	0.03232
7	42 241.7	307.71	0.14985	33 908.9	383.37	0.00000
8	43 602.2	298.09	0.21865	38 320.7	339.3	0.00005
9	45 407.5	286.26	0.02931	40 806.5	318.63	0.00009