MIXED ORGANIC CRYSTALS FOR SCINTILLATION COUNTERS

Journal Article · Sun Jan 01 04:00:00 EST 1961 · Rost Kristallov, Akad. Nauk S.S.S.R., Inst. Krist.

OSTI ID:4760037

Belikova, G S; Belyayev, L M

The mechanism by which mixed organic crystals of im proved luminescence are formed was studied. Mixtures of naphthalene with a luminescent compound were used. The compounds were divided into the following groups: anthi acene- phenantrene-chrysene; diphenyl-p-terphenylquaterphenyl; dibenzyl- stilbene- tolane; 1,4-diphenylbuta1,3-diene (DPB)-1,6-diphenylhexa-1,3,5-triene (DPH)1,1,4,4,-tetraphenylbuta-1,3-diene (TPB); anthranilic acid, methyl anthranilate-N-methyl anthranilic acid-N-phenyl anthranilic acid. The intensity of scintillation was measured by the amplitude method with a scintillation spectrometer. Optical contact between specimens and the photocathode was provided by vaseline. The measurements were carried out with a half-elliptical reflection coated with aluminum. Stilbene monocrystals were used as standards and their scintillation intensity was taken as 100%. The specti a of luminescence were taken on a SF-4 spectrophotometer using the Hg line at 313 m mu . DPB, DPH, anthranilic acid, and methyl anthranilate greatly enhanced the intensity of naphthalene scintillation. The intensity was a function oi concentration, especially at low levels. The region of spectra was displaced to the right, in comparison with that of pure naphthalene. Thus, the spectra of crystals, containing DPB, anthranilic acid, and DPH show principal peaks at 392, 406, and 430 m mu , respectively, compared with 345 m mu from pure naphthalene. The spectra show two peaks; at high concentrations, however, one of them (attributed to naphthalene) vanishes. The results are interpreted in terms of interaction between the two molecules in the crystals. Such interaction is a function of the similarity in structure and depends on the formation of solid solutions. The projection of naphthalene was comparcd with that of the added compounds and the comparisons were in agreement with experimental results. Finally, luminescence is shown to be used as a method of estimating the quantity of the luminescent compound having entered the composition of the crystal. (OTS)

• Research Organization: Originating Research Org. not identified
• NSA Number: NSA-16-032230
• OSTI ID: 4760037
• Journal Information: Rost Kristallov, Akad. Nauk S.S.S.R., Inst. Krist., Journal Name: Rost Kristallov, Akad. Nauk S.S.S.R., Inst. Krist. Vol. Vol: 3
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ANTHRACENE
AROMATICS
CRYSTALS
LUMINESCENCE
MEASURED VALUES
METHYL RADICALS
MIXING
NAPHTHALENE
ORGANIC COMPOUNDS
PHENYL RADICALS
PHYSICS
SCINTILLATION COUNTERS
SPECTROMETERS