The absorption bands of titanium oxide, TiO₂, are the characteristic flutings[300][301] of the stars of Class
, and the strength of these bands has been proposed[302] as a criterion of class for the stars in which they are found. It is perhaps noteworthy that titanium, zirconium, and carbon, the only elements which give oxides in stellar spectra (hydrogen excepted) belong to the fourth group of the periodic system.
VANADIUM (23)
The vanadium lines are best identified by intensity from Rowland’s table. The following multiplets[303] are present in the solar spectrum:
,
,
