Fig. 6.9 Contour plots of the vdW vibrational mode wave functions for the HeI 2 (X, B and
E) states in Jacobi coordinates
HeI 2 E; v E ¼ 0 À 17; n E ¼ 0
hm 2 B; v B ¼ 16 À 19; n B ¼ 0
hm 1 X; 0; n X ¼ 2
ð6:3:2Þ
(see Fig. 6.10) have been studied in [92] (see Figs. 6.11, 6.12) as examples. The
hm 2 laser radiation is produced by mixing of the TDL laser fundamental output and
fundamental harmonic of the YG981C laser in KDP crystal, 1=k 2 ¼ 1=k
0
þ m
i
f (k
0
and m
i
f are generation wavelengths of the TDL laser and wavenumbers of fundamental harmonics of the YG981C laser, respectively). The fundamental YG981C
laser harmonic consists of 4 spectral components: m
1
f ¼ 9395:12 Æ 0:02 cm
À1 , m
2
f ¼
9393:53 Æ 0:07 cm
À1 and m
3
f ¼ 9396:67 Æ 0:10 cm
À1 with relative intensities of
about 1 : 0.3 : 0.05, and a very weak line with the frequency of m
4
f ¼ 9392:04 cm
À1 .
Therefore, the hm 2 laser radiation consists of 4 spectral components, also (see
Sect. 6.2.1.2 in [18]).
6.3 Van der Waals Complexes
217