kimia medisinal

ENERGI HOMO LUMO DAN REAKTIVITAS SENYAWA

I.

Tujuan

1. Mamp Mampu u menghi menghitu tung ng eneg enegii HOMO LUMO LUMO !ai !ai "en#a "en#a$a $a tuun tuunan an %en&' %en&' !engan !engan me'iha me'ihatt ea(ti ea(ti)it )ita" a" !an (e"ta* (e"ta*i'an i'an "uatu "uatu "en#a$a "en#a$a teha! teha!ap ap +aa( +aa( HOMO LUMO. ,. Meng Mengeta etahu huii hu*u hu*ung ngan an anta antaa a ene enegi gi HOMO HOMO LUMO LUMO !eng !engan an ea(t ea(ti) i)it ita" a" "uatu "en#a$a. II. Dasa Dasarr Te Teori ori

HOMO-L HOMO-LUMO UMO /penu /penuh-( h-(&"& &"&ng/ ng/00 O*ita' O*ita' Intea( Intea("i. "i. Suatu Suatu pin"i pin"ip p !a"a "emua 'ang(ah !ai "emua me(ani"me me(ani"me ea("i hete&'#ti2 hete&'#ti2 *ai( 3&n"te! atau atau Le$i Le$i"" ea( ea("i "i a"ama"am-*a *a"a "a mee mee(a (a me'i me'i*at *at(a (an n *ai( *ai( tan tan"%e "%e p&t p&t&n &n 3&n"te!04 atau pa"angan ti!a( !i*agi5intea("i &*ita' (&"&ng Le$i"0. (eti(a &*ita' at&m *eintea("i !ianggap4 ea("i 3&n"te! !apat !i'ihat han#a (a"u" (hu"u" !ai Le$i"4 !imana &*ita' (&"&ng a!a'ah &*ita' anti*&n!ing i(atan H6. Sing(atn#a Sing(atn#a "emua ea("i hete&'#ti2 hete&'#ti2 han#a meupa(an meupa(an 2&nt&h intea("i antaa &*ita' at&m atau m&'e(u' !ii"i !an &*ita' at&m atau m&'e(u' (&"&ng #aitu4 Le$i" ea("i a"am 7 *a"a. Keti(a (ita *eha!apan

!engan *eintea("i

&*ita' m&'e(u'4 !ua #ang *eintea("i umumn#a umumn#a  • • •

Highe"t enegi &22upie! m&'e2u'a &*ita' HOMO0 !ai "atu m&'e(u' L&$e"t enegi un&22upie! m&'e2u'a &*ita' LUMO0 !ai m&'e(u' 'ainn#a. O*ita'-&*ita' a!a'ah pa"angan #ang *e*aing pa'ing !e(at !i enegi !ai "eti "etiap ap "epa "epa"a "ang ng &*i &*ita ta''

•

!a'a !a'am m

!ua !ua

m&'e( &'e(u' u'44

#ang ang

memu memung ng(i (in( n(an an

mee(a.*eintea("i pa'ing (uat. O*ita' O*ita'-&* -&*ita ita'' (a!ang (a!ang-(a -(a!an !ang g !i"e*u !i"e*utt &*ita &*ita'' pe*at pe*ata"an a"an44 (aena (aena untu( untu( mee mee(a (a *e* *e*&h &h&n &ng g pa!a pa!a *ata *ata"" te' te'ua ua !ai !ai e'e( e'e(t t&n &n !ai !ai m&'e m&'e(u (u'' T&""e''4189:0. 3ei(ut a!a'ah intea("i #ang penuh-(&"&ng !igam*a u'ang "e*agai intea("i HOMO-LUMO

Endhayanti Oktovia Hermanto

Page 1

Intea("i antaa "e*uah &*ita' (&"&ng !an "e*uah pa"angan e'e(t&n te+a!i "e2aa e%e(ti% antaa "e*uah HOMO !ai "uatu "pe"ie" !an "e*uah LUMO !ai "pe"ie" #ang 'ain. Ha' ini !in#ata(an "e*agai pin"ip HOMOLUMO !an intea("i antaa "e*uah HOMO !an "e*uah LUMO !i"e*ut "e*agai intea("i HOMO-LUMO. ;e*an!ingan #ang !i'a(u(an teha!ap intea("i HOMO-LUMO pa!a *e*agai "en#a$a mengin!i(a"i(an *ah$a HOMO #ang 'e*ih tinggi !an LUMO #ang 'e*ih en!ah mem*ei(an pemi"ahan enegi #ang 'e*ih (e2i' untu( men+a!i "e*uah (&m*ina"i peneima e'e(t&n !an pem*ei e'e(t&n untu( tan"%e muatan atau tan"%e e'e(t&n Si"$an!&n& !an S&e(a!+&4 ,<<90. Ke2en!eungann#a !apat !iing(a" "e*agai *ei(ut •

;em*eian e'e(t&n pa!a "pe"ie" #ang 'ain pa'ing mu!ah te+a!i pa!a

•

HOMO. ;eneimaan e'e(t&n !ai "pe"ie" #ang 'ain pa'ing mu!ah te+a!i pa!a

•

LUMO. HOMO #ang 'e*ih tinggi enegi i&ni"a"i #ang 'e*ih (e2i'0 mem*ei(an (emampuan #ang 'e*ih (uat untu( mem*ei(an e'e(t&n pa!a "pe"ie" #ang

•

'ain. LUMO #ang 'e*ih en!ah a%inita" e'e(t&n #ang 'e*ih *e"a0 mem*ei(an (emampuan #ang 'e*ih (uat untu( meneima e'e(t&n !ai "pe"ie" #ang 'ain.


Page 2

•

LUMO #ang 'e*ih tinggi !an HOMO #ang 'e*ih en!ah a(an mem*ei(an(emampuan #ang 'e*ih en!ah pa!a (emampuan untu( meneima atau mem*ei(an e'e(t&n. 3i'angan &(upa"i e'e(t&n !a'am "e*uah &*ita' e'e(t&n #ang ti!a(

*epa"angan a!a'ah tetentu #aitu "etengah !ai *i'angan &(upa"i ma("imum e'e(t&n !an !engan !emi(ian +eni" &*ita' ini !i"e*ut "e*agai &*ita' m&'e(u' #ang !itempati "e2aa tungga' Singly-occupied molecular orbital -SOMO0. Keea(ti%an #ang (hu"u" !ai &*ita' e'e(t&n #ang ti!a( *epa"angan SOMO0 !engan +eni" (&n%igua"i e'e(t&n *ia"a !i"amping pin"ip HOMO LUMO !an pin"ip intea("i tan"%e muatan mem*ei(an in!i(a"i *ah$a peanan (un2i !a'am ea("i (imia !imain(an &'eh HOMO4 LUMO !an SOMO. Ketiga +eni" &*ita' ini !i"e*ut "e*agai &*ita' te!epan  frontier orbital 0 !an te&i #ang men2atat peanan !ai &*ita'-&*ita' ini !i"e*ut "e*agai te&i &*ita' te!epan. Dengan met&!e (&mputa"i4 pehitungan enegi a(an !apat !itentu(an4 teutama !a'am penentuan enegi HOMO Highe"t O22upie! M&'e2u'a O*ita'"0 !an enegi LUMO L&$e"t Un&22upie! M&'e2u'a O*ita'"04 "ehingga 2e'ah enegi !i !apat !iumu"(an "e'i"ih antaa enegi LUMO ELUMO0 !engan enegi HOMO EHOMO0 D$i ;an&$&4 ,<<,0. Yang penting a!a'ah &*ita' m&'e(u' #ang pa'ing tetinggi enegi0 &*ita' m&'e(u' !itempati HOMO0

!an teen!ah enegi0 &*ita' m&'e(u'

!itempai LUMO0. Ini a!a'ah &*ita' #ang pa'ing mung(in te'i*at !a 'a m e a( "i (i mia. Untu( a'a"an ini4 &*ita' m&'e(u' pa!a umumn#a !iu+u( !ai &*ita' HOMO atau L U M O . S a t u (euntungan +e'a" te&i &*ita' at&m ata" te&i i(atan )a'en"i a!a'ah *ah$a e'e(t&n!apat te!e'&(a 'i"a"i. 3eati *ah$a e'e(t&n !a'am &*ita' at&m ti!a( te*ata" pa!a uang antaa !ua at&m. Sa'ah "atu 2aa *epi(i tentang !e'&(a'i"a"i a!a'ah *ah$a ha' itu miip !engan e"&nan"i enegi !ai te&i i(atan )a'en"i. M&%%ett4 ,<<=0.


Page 3

III.

Hasil Pengamatan a. 3ei(ut meupa(an "tu(tu (imia !an m&!e' tiga !imen"i !ai !ei)at %en&'.

Substituen

Struktur Kimia

Model 3D

HO

H phen&'

HO

>-Me >-meth#'phen&'

OH

>-?,H@ >-eth#'phen&'

OH

>-?H= >-p&p#'phen&'


Page 4

OH

>-?>H8 >-*ut#'phen&'

>-?@H11

HO

>-pent#'phen&' OH

>-?=H1@ >-hept#'phen&' OH

>-?9H1= >-&2t#'phen&'

>-?8H18 HO

>-n&n#'phen&' OH

>-??H0 >-i"&*ut#'phen&'


Page 5

HO

OH

>-OH >-h#!&B#'phen&'

O

OH

>-O?H >-meth&B#'phen&' O

OH

>-?HO >-h#!&B#*enCa'!eh#!e

N

OH

>-?N >-h#!&B#*enC&niti'e

*. Ta*e' HOMO 7 LUMO  Sen#a$

Su*"tituen

E HOMO

E LUMO

E LUMO - E

a

60

eV0

eV0

HOMO

1

H

-84>8<

<4<@

84@><

,

>-Me

-84><>

-<4<1,

848,



>-?,H@

-84>>8

-<4<,1

84>,9

>

>-?H=

-84><<

-<4<<>

848:

@

>-?>H8

-84>9

<4<

8491

=

>-?@H11

-84>><

-<4<<9

84>,

9

>-?9H1=

-84>>@

-<4<<9

84>=

8

>-?8H18

-84>8

<4<

849,


Page 6

1<

>-??H0

-84>=

<4<<1

84>9

11

>-OH

-84,<=

-<4<<,

84,<@

1,

>-O?H

-84>,

-<41>=

84,9@

1

>-?HO

-84:

-<4@>,

84<81

1>

>-?N

-849@8

-<4>:8

848

2. GA; tetinggi hingga teen!ah  Sen#a$

Su*"tituen

E HOMO

E LUMO

GA;

a

60

eV0

eV0

E LUMO - EHOMO

1.

H

-84>8<

<4<@

84@><

,.

>-??H0

-84>=

<4<<1

84>9

.

>-?9H1=

-84>>@

-<4<<9

84>=

>.

>-?@H11

-84>><

-<4<<9

84>,

@.

>-?,H@

-84>>8

-<4<,1

84>,9

:.

>-?H=

-84><<

-<4<<>

848:

=.

>-Me

-84><>

-<4<1,

848,

9.

>-?N

-849@8

-<4>:8

848<

8.

>-?8H18

-84>8

<4<

849,

1<.

>-?>H8

-84>9

<4<

8491

11.

>-O?H

-84>,

-<41>=

84,9@

1,.

>-OH

-84,<=

-<4<<,

84,<@

1.

>-?HO

-84:

-<4@>,

84<81


Page 7

IV.

Pembahasan

;a!a pa(ti(um (a'i ini !i'a(u(an mengenai enegi HOMO - LUMO "eta ea(ti)ita" "en#a$an#a4 #ang *etu+uan !apat menghitung "a'ah "atu paamete e'e(t&ni( HOMO - LUMO !ai "en#a$a tuunan %en&' !an !apat mengetahui

hu*ungan

enegi

HOMO

-

LUMO

!engan

ea(ti)ita"

"en#a$an#a. HOMO - LUMO meupa(an pa"angan &*ita' #ang memi'i(i enegi pa'ing *e!e(atan !ai (e!ua m&'e(u' #ang *ei(atan pa'ing mem*ang(it(an (e!uan#a *eintea("i. Diantaa &*ita' m&'e(u' tei"i HOMO !an m&'e(u' ti!a( tei"i LUMO te!apat gan!gap #aitu "e'i"ih HOMO !an LUMO. ;a!a pin"ip HOMO-LUMO a!a'ah intea("i antaa "e*uah &*ita' (&"&ng !an "e*uah pa"angan e'e(t&n te+a!i "e2aa e%e(ti% antaa "e*uah HOMO !ai "uatu "pe"ie" !an "e*uah LUMO !ai "pe"ie" 'ain. ;e*an!ingan #ang !i'a(u(an teha!ap intea("i HOMO-LUMO pa!a *e*agai "en#a$a mengin!i(a"i(an *ah$a HOMO #ang 'e*ih tinggi !an LUMO #ang 'e*ih en!ah mem*ei(an pemi"ahan enegi #ang 'e*ih (e2i' untu( men+a!i "e*uah (&m*ina"i peneima e'e(t&n !an pem*ei e'e(t&n untu( tan"%e muatan atau tan"%e e'e(t&n. Dai pa(ti(um !ipe&'eh ha"i' !ai pehitungan !engan "en#a$a tuunan %en&'. Ni'ai tetinggi HOMO (e ni'ai teen!ah HOMO4 pa!a "en#a$a >-OH !an ni'ai teen!ah pa!a "en#a$a >-?N.Da'am ha' ini "en#a$a HOMO 'e*ih memung(in(an "e*agai !&n& e'e(t&n !an pen!&&ng e'e(t&n4 (aena HOMO #ang 'e*ih tinggi memi'i(i enegi i&ni"a"i #ang 'e*ih (e2i' "ehingga mem*ei(an (emampuan #ang 'e*ih (uat untu( mem*ei e'e(t&n pa!a "pe"ie" #ang 'ain. 3e!a"a(an ha' te"e*ut pa!a ta*e'4 ma(a !apat !i"impu'(an "e'i"ih enegi #ang &*ita' HOMO - LUMO memu!ah(an menggam*a(an "uatu "i"tem *e'a(u untu( menga'ami (ea!aan e'e(t&ni( #ang 'e*ih tinggi. Se'i"ih Endhayanti Oktovia Hermanto

Page 8

enegi &*ita' HOMO - LUMO #ang 'e*ih en!ah menggam*a(an "uatu "i"tem *ea!a !i "i"tem e'e(t&n #ang tinggi. Se!ang(an LUMO teen!ah memi'i(i a%inita" #ang 'e*ih *e"a4 "ehingga mem*ei(an (emampuan #ang 'e*ih (uat untu( meneima e'e(t&n !ai "pe"ie" 'ain. Se'an+utn#a untu( ni'ai gap !ipe&'eh ni'ai teen!ah pa!a "en#a$a >-?HO !engan ni'ai 84<81 !an ni'ai tetinggi pa!a "en#a$a H !engan ni'ai "e*e"a 84@><. Sen#a$a #ang memi'i(i ni'ai GA; tetinggi hingga teen!ah a!a'ah hi!&("i %en&'4 >-i"&*uti' %en&'4 >-n&ni' %en&'4 >-penti' %en&'4 >-p&pi' %en&'4 >metan&' %en&'4 >-hi!&("i*enC&niti'4 >-n&ni' %en&'4 >-*uti' %en&'4 >-met&("i %en&'4 >-hi!&("i %en&' !an >-hi!&("i'*enCa'!ehi!. Da'am ha' ini "ema(in (e2i' gap atau +aa( antaa HOMO !an LUMO ma(a a(an "ema(in mu!ah e'e(t&n a(an tee("ita"i. Sehingga a(an 'e*ih ea(ti% pu'a intea("in#a. ;e*an!ingan intea("i HOMO LUMO pa!a *e*agai "en#a$a mengin!i(a"i(an *ah$a HOMO #ang 'e*ih tinggi !an LUMO #ang 'e*ih en!ah mem*ei(an pemi"ahan enegi #ang 'e*ih (e2i' untu( men+a!i "e*uah (&m*ina"i. ;eneima e'e(t&n !an pem*ei e'e(t&n untu( tan"%e muatan5e'e(t&n. a!i "en#a$a >-?HO #ang memi'i(i gap te(e2i' #ang 'e*ih mu!ah te+a!in#a tan"%e e'e(t&n atau tee("ita"i e'e(t&n.

V. Kesimpulan

3e!a"a(an ha"i' pa(ti(um #ang te'ah !i'a(u(an !apat !i"impu'(an *ah$a  1. Sen#a$a #ang memi'i(i ni'ai GA; tetinggi hingga teen!ah a!a'ah hi!&("i %en&'4 >-i"&*uti' %en&'4 >-n&ni' %en&'4 >-penti' %en&'4 >-p&pi' %en&'4 >-metan&' %en&'4 >-hi!&("i*enC&niti'4 >-n&ni' %en&'4 >-*uti' %en&'4 >-met&("i %en&'4 >-hi!&("i %en&' !an >-hi!&("i'*enCa'!ehi!. Endhayanti Oktovia Hermanto

Page 9

,. HOMO #ang 'e*ih tinggi memi'i(i enegi i&ni"a"i #ang 'e*ih (e2i' "ehingga mem*ei(an (emampuan #ang 'e*ih (uat untu( mem*ei e'e(t&n pa!a "pe"ie" #ang 'ain. Se!ang(an LUMO teen!ah memi'i(i a%inita" #ang 'e*ih *e"a4 "ehingga mem*ei(an (emampuan #ang 'e*ih (uat untu( meneima e'e(t&n !ai "pe"ie" 'ain. VI.

Daftar Pustaka 1. D$i ;an&$&4 Han&. ,<<,. Pengantar Kimia Komputasi Austrian -

Indonesian Centre for Computational Chemistry (AIC). Y&g#a(ata  Kimia MI;A UGM. ,. M &% %e tt 4 T .4 M . , < <= . Molecular rbital !heory. ;'at"*ugh USA  SUNY ;'att"*ugh. . Si"$an!&n& !an S&e(a!+&. ,<<9. Kimia Medisinal . Sua*a#a  Ai'angga Uni)e"it# ;e"". >. T&" " e ' '4  . A. 1 89 : . "uantum Mechanics.Ma#'an! USA Uni)e"it# &% Ma#'an!.


Page 10

kimia medisinal

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