Abstract
The photophysical properties of two
N,
N′-bis-alkyl-1,4,6,8-naphthalenediimide (DCN1 and DCN2) have been studied in chloroform and
N,
N-dimethylformamide solvents. The ability of DCN2 in
N,
N-dimethylformamide to detect metal cations have been monitored by the fluorescence emission spectroscopy. It has been shown that the fluorescent intensity is very sensitive to the concentration of Fe
3+ cations. The reaction of iodine with
N,
N′-bis-alkyl-1,4,6,8-naphthalenediimide in chloroform solution have been investigated by spectrophotometric method. The results indicate the formation of two CT-complexes [(DCN1)I]
+·I
3
− and [(DCN2)I]
+·I
3
− at donor:acceptor molar ratio of 1:2. The [(DCN1)I]
+·I
3
− shows the characteristic absorptions of I
3
− ion at 290 and 360
nm while the charge-transfer transition of [(DCN2)I]
+·I
3
− occurs at 310
nm. Three characteristic bands at the far infrared region in each iodine complex are observed around 135, 105 and 85
cm
−1 due to
ν
as (I–I),
ν
s (I–I) and
δ (I
3
−), respectively with
C
2v symmetry. The values of the complex formation constant,
K, and the absorptivity,
ɛ have been calculated.