A new band system involving a frequency of 165·1 cm.⁻¹ in the excited state of the molecule is discovered in the absorption spectrum of iodine as measured by Cordes. This locates an electronic level at 51683 cm.⁻¹ above the ground level. The P-R, K-M bands form very probably a different system with a lower electronic level for their excited state. The dissociation products of the initial states of both the systems are however identical,viz., I⁻(¹S₀)+I⁺(³P₂). The nature of the transitions giving rise to these two systems is discussed.

Among the diffuse fluctuation bands observed in the emission spectrum of iodine, there are five groups each of which involves a frequency difference of about 165 cm.⁻¹ among the component bands. An interpretation of these five groups is given, which shows that they are due to transitions from a common initial level to five different final levels. The initial level is identified with the newly discovered level 0_u⁺ at 51683 cm⁻¹. The five different final levels are identified with just those states whose energies and nature can be calculated theoretically. All these are repulsive states with potential energy curves of varying slopes. The occurrence of bands (3945·6 and 3919·4 A) in the second group and of bands (3879·9 and 3855·8 A) in the third group clearly shows that the coupling conditions in I₂ are of Hund’s case (c).

The spectra of a number ofp-disubstituted benzenes were analyzed earlier by Richards and Schaeffer by assuming that the twometa H-H coupling constants are equal and thepara H-H coupling constant is zero. In the present work a method for analysing this type of spectra, without making any simplifying assumptions, is proposed. The proton resonance spectra ofp-bromochlorobenzene,p-chlorotoluene andp-chloroiodobenzene were obtained and analyzed as examples, and all the parameters were determined in each case. The general form of this type of spectra for different values of chemical shift is discussed.

The leaves ofRhododendron grande Wight have been examined for their chemical constituents. Campanulin and friedelin were obtained from the petroleum ether extract, ursolic acid from the ether extract and quercetin and a minor component from the alcoholic extract.

Taxifolin (a dihydro flavonol) and a procyanidin have been isolated from the stem bark ofRhododendron grande Wight. It is of special interest that they represent neighbouring stages in the biogenetic evolution of polyphenols. The procyanidin occurs as a dimer for which probable structures are proposed based upon chemical and spectral evidence. This dimer represents a new type.