Absorption by molecular excitation H H

Transcription

1 Absoptio by oleula exitatio H H H

2 Classial Motio ad Rotatio li v is ass v is veloity p v p is oetu p ot L ot I I is oet of ietia is obital veloity I L is obital oetu v L I ot Mass of Movig Body v Liea oetu: p= v ass: I=

3 Rotatio i the Uivese ehaial tools oleules ulei hados otatios/se etifuge sideeal otatio galaxy lustes euto stas wate galaxies _ q q eso plaets L v I v Adoeda - - typial size Satu

4 Rotatioal exitatio odes...,3,,, 4 4 h I L I L ot ot Diffeet levels of otatioal exitatio fo di-atoi oleules, haateisti otatioal bad of the oleule. s J h 34.55

5 xaple: oleule 4,,,3, au 9au Js 7.66 kg 8 Hz Hz ,,,3, The fequey o wavelegth of the oespodig absoptio lies is typially i the iowave egio of the eletoageti spetu.

6 xaple: C oleule 4 I I 6 bod,,,3,... C ato bod 6 I I C C C C 6.8, C bod ato kg.56 kg 4.9 kg Js kg Hz., C 6 8,,3,... C , The fequey o wavelegth of the oespodig absoptio lies is agai i the iowave egio of the eletoageti spetu. C. ato

7 Liea exitatio odes: vibatio x x x xtesio of spig oespods to ass x g x If eleased afte extedig the spig by a legth of x, a osillatio ous with a fixed fequey ad peiod T. The extesio x deteies the aplitude A of the osillatio. T spig ostat depeds o spig speifi paaetes

8 stethig bedig twistig sissoig Stethig ode betwee oleules k h ; Photo eegy Wave ube is spig ostat fo a oleule; it eflets the stegth of heial bodig: uits : N/=kg/s Is the doiat ehais fo absoptio M adiatio absoptio i the atosphee Moleula xitatio Modes / s kg s kg x g

9 xaple: oleule / / / What is the fequey o wavelegth assoiated of a oleules with a vibatioal ostat of =33 kg/s alulated as haoi osillato? = he /Δx Δx h h Quatizatio o iosopi level:

10 / / / / au /.5 s / /.37 s s kg 33 s 7 kg au / 4, 8,4.8.7 /.5 3 s 5.4, 8.47,5.8 This oespods to wavelegths i the ifaed age of the eletoageti spetu. By absoptio of ifaed photos with these wavelegths oleules stat vibatig ad stoe the oespodig aout of eegy.

11 xaple C oleule / / 86 N / Asyeti steth ode asy 4. 6 bed /.33 / kg 86 s , 7 kg /.55,.9 4 Hz.93 sy 7. ostats fo diffeet odes: k ode ode ode

12 Diffeet absoptio opoets Coss setio fo absoptio evet ieases at absoptio eegy as esoae Loetz shape. Sigle tasitio oespodig to photo absoptio ad exitatio to a vibatioal state. This is obseved as sigle absoptio esoaes. Rotatioal bad ode, oespods to a ovelap of vibatioal exitatio states with a bad of otatioal states build o top. This is obseved as seveal bads of ay ovelappig esoaes. Cotiuous eegy loss of photos due to satteig. This is a wavelegth o eegy idepedet, o-esoat poess that affets wide egios of ioig light.

13 Ifaed exitatios Relies o vibatioal odes of diffeet oleules Ifaed odes Ifaed light eflets diffeet odes of vibatio & otatio of oleules Photos with wavelegths that oespod to the vibatioal odes of oleula gases ae beig absobed fo ioig photo flux. This is efleted i absoptio lies i the photo spetu!

14 Total absoptio eegy i i tot sat ot vib tot h i sat vib ot i i i i i dx x abs dx x tas x x x e e,,, Absoptio Tasissio

15 Lie shape ad haateistis C absoptio lie at k=/=667 - I Absoptio lies ae haateized by: positio eegy, stegth itesity, width ediu =4.99 bedig ode k=α=6 - Lie width oespods to pessue boadeig due to oleule ollisios ad Dopple boadeig due to diffeees i theal veloity ad dietio of oleules. f k k P, T k k P P / T T fk-k shape fato of lie α is efeee width fo T =73, P =3 b.. half width at P,T oditios depedig o the gas; α =.7 - fo C

16 Tasissio T Absoptio oeffiiet ad tasissio k k k, x i x i i.. Absoptio Tasitio σ Seies Pessue &Dopple boadeig σ k Tasissio Spetu k Seies Seies3. tas abs e, x dx e, x dx Wave ube k

17 Tasissio ad Absoptio dx x tas abs dx x tas tas e e,,

18 Ipat of C abudae