&%mhw,lre - Raman Research Institutedspace.rri.res.in/bitstream/2289/3787/10/Chapter 6.pdf · 2017....
Transcript of &%mhw,lre - Raman Research Institutedspace.rri.res.in/bitstream/2289/3787/10/Chapter 6.pdf · 2017....
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FIG. la: ( I q a F f s r n between 1 coo 8 1 and the values obtained by retaining; terms ul, t o d i f f e r e n t even Itisgadre golynosPials in the expanrrion of \COB E)\.
B I G . 1M: C q a r i o on be tween ( s in @\and tho vcSuca obtaimd by retaining terms up to different even Legendre polynomialn i n the expansion of lrin el.
FIG. l c : Comparison between E(8) and the values obtained by retaining terns up t o Oifferent even Gegendre polynamials in the expamion of E ( 0 ) .
Pt %a dllc.wr fLgums %hiat the wm radmd
ur%r *Q
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en%W o f oa1,wa o f Q lca), w W 3 s the! @xmr &E
\@as t3 \ stul raad.n. sa4ilcesble far ~ J a o (Fig. la).
Aa we ha% eeaa &a 1-t Glwa chezptaxm, tM izurZunivxtr of
af 42q$dPlnd*~, we,
aha3.X saa that M e ~ ~ ( o o e 43) tara &a 86\smt;idL t o got
a ~ u ~ . I & % & ~ v ~ X Y ar~~aa1S S~D, W W . -Ma have
W o c%iikear3;i~'t;;;t up to P2(coa B) . P ~ ( C O B e) ma ~ ~ ( c o e 9) resgeotivd21. In tho apa=ion. ( 7 )
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instanos, ad^ ~ b . fircli t in oq. (7) ma o i i r ~ ~
'16,11%a 0 . ,i(P2) * % a&% 90 the gI f~Prdf1ai y-
a8 -Q~&I)= oi' f j l a m rraoPrjr &!a i&g* a* 'tiiks Esm *&&ti am
F10.2: Variation of (P2), dnem and llf'/~ aa functions of B obtained by retaining terms up to P2(cos (3) in the expansions of angle dependent terns.
9,42B for W < 0,4 ;tin figasa J. S&we& h-Je ot)p?~a~and
to oaloulaYono aaO. bp rstPlniw tccrou up %a ~ ~ i a w G ) ,
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a t the Ex Urn p-t A n i i w W 4ii-OQI*
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for tho eslZircb r-8 of wa2uet~ at R, 'IPh-:h (d) = O 9w 6.
P 0.5, ~ ~ ( 4 ) a d ~ ~ ( 4 ) stilX crontributs to +he s t & l X A *
OF the no%cntlc pblSe, 3%- b&, Ta, it 3s *sea dh&t m Ti-
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systan o f r&.ight c i ~ a e ag~ndaza i s r 0.91. ~a b v o
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alnoe tjr ~ ~ l l o u l & t e Q W u e US 4U, caxca~a G.41 In W r w e .
%is ungEy.altool 3cmrr2E &@ ~ w r w e d Qy Ue3,uBiw the @*fpm
oxder ternr iio la eeen in f&oree 3b and 3c, and dam at &I
gs&.nt i8 a aaisa$oatl?o Pax flfc2O.4.t. It mum Qt9f Pba~i~ EBPILSEIQ- -
. FIG. 3a: Variation of (P2) , dnen and obtained
by retaining terms up t o p2 (COB 0 ) in the expaneions of angle dependent term and p lo t t ed ita functions of 2R (for ~ > 0 . 5 ) and 1 1 2 ~ (for ~ ( 0 . 5 ) .
. PIO.3b: Variation of <p2) , (P~) , dnem and A?/F obtained by rstdnizqg terns up t o ~ ~ ( c o s 0 ) in the expandons of w e dependant t e r m .
mO.30: Var iu t iom of (P~) , (p4) . (B6) , dnam and AP/p obtained by r c t t a i n l ~ ~ g terms up to
' 6 ( coo 8 ) I n the expanaimla uf mgle dependent terns.
FIG.4a: &/Ilk, ~ v / k l and $ obtained by retaining terms up to p2(coe €3) in tho expansions of aslg3.e dep enden3 terzlis.
FIG.4b: k PV@T and $ obtetned by retaiaiw term up t o P ~ ( C O S 0 ) Zn the expansions of angle
dependent t erns .
IFIG.4c: da'bs, PP@ and $ obtained by retainio~( terms up to p6(coe 0 ) in the elgansiona of angle dependent terns.
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only up t o ~ ~ ( ~ 0 8 B)
in expanaton, A?& epgraaohaa -0. Inohiiing terms
to 8 ) ( f i g * 3b) and P ~ ( @ W B) (f~g.34~). A ~ P
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(Pa) in a a m U range oi vIk3w~ o f ZR w m t x 2W m 1. ds
28 rp~roaohsa the rii lus 5 1.0 I U2@) bee
d l e r . Hame to get the liI tr-m~ftion, <?& It;o
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( ' /~")r*a-x~u harfng the asme rdua of &,, at the
at*&= a ##a%imm d w r ~ s a @haply a%ta&abg a ia&nA&mas
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Ewers fZ9 a !3b ekzSBdt raf lgw i ti :sn
groputieu when tlte ex~)ru.&ion i a rcrttr$.icted :u .??;coo *C B)
and %w &a aaaunad t D Ba 0. G a'; 22j:rI. reca l l fFwk
f b ~ e is 3 ~ ~ ~ c ~ ~ ~ s P I A , $ % ~ f3ik t~&,%.*T;i@l'& ,az.cpaS?tAii.:: 92WU!
gZ r̂ 0, S filr ar qyfat.cpm o f c ; r U , " ~ d ~ L ::;iP ~t3L.a rt.ili?s, ~ f f na0 7 the #xl,ootr~$io p8mE 02 %>ta ~ O % C F I % " , ~ : L J * f e s 3ci:a ,Pop 2. II. Q.5
u b @ ~ (9! 0 (OW $A&. 3iil. &L.%!xEI. $3 Uli.2 C330 i s H
& p p ~ ~ a ~ h & 3 3.5 I ? ~ F ~ Q eA";Pser s i d e , %I@ ;x~C'kis& 3ai%$~a21, t&@
t o e x ~ e c i the c3me~% ;~aak& & t 3 ~ ~ i 1 3 1 * 3 u t by L : + x ~ I , u & A ~
the et t raat ive potent id ( o2 # % 6 d ) aw bto
PI0.58: (P~) , 02/vOk end $dv0k obtained by includLng an attractive potentical an4 re tdning terms up t o p2(cos 8) in the erpsnsioas of angle dependent tcrma and fixing dnem = 0.6.
FIG. 5b. DPl F , Q U ~ ~ T and + o~ta ineci by includiw an attractive potential &nd re t u b i n g t e r m s up t o ~ ~ ( c o e 43) in the expansions of an@e dependent terms and fixing Sam = 0.6.
rnrr 1 0.0 OIO ~a~aulutionxs near Be 0.5 are a d pwmibla
similar.. UnWrr in the h.Fd y ~ ~ t i o l e aystsm, <I?&> ia
lees than <PI> rtLtah i(wU l a hpio than (P2> fox all
FIG.6a: (P~) , (P~) , {P~) , OdvOk and O 2 b 0 k obtained by including an attractive potential and retaining term up t o ~ ~ ( c o s 8 ) in athe expansf 0x18 of angle - dependent term an3 fixing 4, 10.6.
FI0.6b: AP/p , Au/&!E and f3 obtaned by inoludtng an attractive potentiel and ratainlag term up t o ~ ~ ( ~ 9 8 B) in the erpan- alone of a w e dependent tena. and fixing dnem = 0.6. -
t N- 2.4 f u r rad-Uk@ rndhenrlaa and at 2s N- 2.4 ~ G G ? disc-
FIG.7a: (P~) , (P~) , (P6) . $/v,k and %/v,k obtained by including an attractive poten t ia l and re tdn ing terms up to p6(coe 8 ) in t h e expansfa of a w e dependant term and fixing dnem = 0.6.
FIG.7b: bf'/u . A u / m t T and $ obtained by including an attractive potential and retaining temo up t o p6(co8 8) in the expand ons of angle dependent terns and fixing dnee 0.4.
FIG.8a: Chemical f omrmla of hexa-nlkayhen~oat ea of triphenylene
PIG.833 Structure of a d i s c o t i c nematic phase.
F I G . 8c : Chemical f onrmla of hexa-n-alkanoateie of truxene
~ e a X rplole~arr ham six Q M ~ ar paiptte-q? wi%h a
s.xw-m M a far p p z - & i - w
zrm f79+jQ t o "1*9 a* b4mz?ea#m
AP ~ m v e d by en ayyram\te arpmaafon Pzr vcxc2- Gala-
a vaXu.s dbas %Q 1. X t @%air* imr4fuil-y the d l t ~ L i e - ~
of x la dccreoctab fisther aad beki~ei t ~ ~ i i c t l y in
%kt@ sppmite r, qunlita%iocs hetrirvfour of fir,$
M'kd 32P) f~,ff0*&03'M d St Wk8IQ@3Q& 3U3: ~@tl&kWr
tho numb= of t- mW~18b in U;Q exqi,walon o f YlrjnXOE.
Efg ~ Z W X U L ~ S ~ & $J1 &.~;~TPO%,%- g * ~ f ~ t L k e J t %hay i rda ~ ~ 3 , ~ -
~atiotls for x 1 ~552 by rdwtiry; da Q;, to bwt
T 403% 4.O at BI~F o t i m r pro~ertiom; ot
are C w a t o b. (P2) 0.595. s,, 3; 3 G*478p fyJfF ;.i~.E64 sad Bhnr = o.97J. par eilnc widus of r by
fixLng $I * G O J T aOC = 0.6 nt '+t. WB iet IL
< 0.45. A?/F * Q.0024 turd &&klk 0.34. Le. , u