Raman Effect in Gases : I.
Sowe B:-cperi/mc?ttol Results.
(Received for pzrblicatiom, 29t h A T I ~ u . 1931
s ~ , .)
With a apmiallp coastrncbed sppmtas the Ramm &at in Puions
simple p e s , aia., TIp, Qg, N,, CO,, N,O, C,H,, SH,, sad SO, brs
been studid st pressures ranging np to 60 nkmospheres, using tbs oieible
radiations of the mercury am for excitation, The fsequenciee are in very
good agreement with those reported by Raeetti and others.
By carefully eliminating tbc psrnsitio light, stirnates of the s b l n t b
intensities and polarisation characters of the Raman lines am mda, It is
found tbat those lines that represent eibntianal tnasitioae em amlly
wd1 poladsed whergas those that arise from mtntional traasitioae sra wry
imparfwtly plarised.
In~eet~igatione
at different prcswres s h o d tbat p m a n b~ r marked
influenno on the ehsrpnees of the robfiord Raman line& It i s foand
that ~ h v IeI oarkin preware, the mll m l v e d rotational fins Ptraetum on
either side of the exoiting Iina L m p l d by b d n n m l v e d bsada. This
preseam ia different for different gam and mmpnda to a stPffcl where the
frequency of collision eqnale the frqnenoy of molecular rotation in tbs om
quantum state.
The specie1 srranpment m d a for eliminating the refl&d liigbt
enabled the photographing of the mtbd a p t r n in all tbs c#8ee witboat
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