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Only three lines observed R(0) R(1) P(1)
The detection of R(1) and P(1) indicates T> 0K Harry Kroto 2004
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Only three lines observed R(0) R(1) P(1)
The detection of R(1) and P(1) indicates T> 0K l Io I I I = Ioe- l I = Io (1 - l + …) Io - I = I ~ l Harry Kroto 2004
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IR(1) /IR(0) ~ R(1) /R(0)
Only three lines observed R(0) R(1) P(1) The detection of R(1) and P(1) indicates T> 0K l Io I I I = Ioe- l I = Io (1 - l + …) (Io – I)/ Io = I/ Io ~ l IR(1) /IR(0) ~ R(1) /R(0) Harry Kroto 2004
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IR(1) /IR(0) ~ R(1) /R(0)
Only three lines observed R(0) R(1) P(1) The detection of R(1) and P(1) indicates T> 0K l Io I I I = Ioe- l I = Io (1 - l + …) (Io – I)/ Io = I/ Io ~ l IR(1) /IR(0) ~ R(1) /R(0) Harry Kroto 2004
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IR(1) /IR(0) ~ R(1) /R(0)
Only three lines observed R(0) R(1) P(1) The detection of R(1) and P(1) indicates T> 0K l Io I I I = Ioe- l I = Io (1 - l + …) (Io – I)/ Io = I/ Io ~ l IR(1) /IR(0) ~ R(1) /R(0) Harry Kroto 2004
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IR(1) /IR(0) ~ R(1) /R(0)
Only three lines observed R(0) R(1) P(1) The detection of R(1) and P(1) indicates T> 0K l Io I I I = Ioe- l I = Io (1 - l + …) (Io – I)/ Io = I/ Io ~ l IR(1) /IR(0) ~ R(1) /R(0) Harry Kroto 2004
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Fermi’s Golden Rule x Io I l Harry Kroto 2004
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Beer Lambert Law I= Io e-l
Fermi’s Golden Rule x Io I l Beer Lambert Law I= Io e-l Harry Kroto 2004
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Beer Lambert Law I= Io e-l
Fermi’s Golden Rule x Io I l Beer Lambert Law I= Io e-l Harry Kroto 2004
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Beer Lambert Law I= Io e-l
Fermi’s Golden Rule x Io I l Beer Lambert Law I= Io e-l Harry Kroto 2004
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Beer Lambert law I= Io e-l
Fermi’s Golden Rule x Io I l Beer Lambert law I= Io e-l Harry Kroto 2004
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Beer Lambert law I= Io e-l is the absorption coefficient
Fermi’s Golden Rule x Io I l Beer Lambert law I= Io e-l is the absorption coefficient = (83/3hc)n em 2 (Nm-Nn)(o-) Harry Kroto 2004
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= (4/3ħc) n em2 (Nm-Nn) (o-)
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= (4/3ħc) n em2 (Nm-Nn) (o-)
① Square of the transition moment n em2 Harry Kroto 2004
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= (4/3ħc) n em2 (Nm-Nn) (o-)
① ② Square of the transition moment n em2 Frequency of the light Harry Kroto 2004
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= (4/3ħc) n em2 (Nm-Nn) (o-)
① ② ③ Square of the transition moment n em2 Frequency of the light Population difference (Nm- Nn) Harry Kroto 2004
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= (4/3ħc) n em2 (Nm-Nn) (o-)
① ② ③ ④ Square of the transition moment n em2 Frequency of the light Population difference (Nm- Nn) Resonance factor - Dirac delta function (0) = 1 Harry Kroto 2004
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C Solution > Energy Levels
For the H atom we shall just use the Bohr result E(n) = - R/n2 D Selection Rules n no restriction l = ±1 E Transition Frequencies E = - R[ 1/n22 – 1/n12] Harry Kroto 2004
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Hot gas cloud –the famous Orion Nebulae
At the centre is the Trapezium Cluster of very hot new stars Harry Kroto 2004
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2b = 103/n yrs per collision 3b = 1023/n2 yrs per collision
Collisions in the Interstellat Medium ISM In space the pressures are low Very low If n = number of molecules per cc (mainly H) then 2b = 103/n yrs per collision 3b = 1023/n2 yrs per collision Number densities are anything from n = Harry Kroto 2004
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Einstein Coefficients
Bn<-m m Harry Kroto 2004
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Einstein Coefficients
Bn<-m Bn->m m Harry Kroto 2004
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An->m/ Bn->m = 8h3/c 3
Einstein Coefficients n Bn<-m Bn->m An->m m An->m/ Bn->m = 8h3/c 3 Harry Kroto 2004
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Einstein Coefficients
Bn<-m Bn->m An->m m A = 1.2 x 3 n em2 transitions per sec Spontaneous emission lifetime (sec) = 1/A = 1037/3 sec Harry Kroto 2004
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(sec) = 1037/3 (cm-1) (Hz) 3 (Hz3) (sec)
H (1420 MHz) cm x x * H2CO rotations cm x x CO2 vibrations x x Na D electronic nm 2x x x H Lyman nm x x Calculations assume e = 1Debye yr = 3 x 107 sec * magnetic dipole Harry Kroto 2004
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Bohr radius an = aon ao = 0.05 nm Harry Kroto 2004
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Bohr radius an = aon2 ao = 0.05 nm Calculate a10, a100 and a300 in cm
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Bohr radius an = aon2 ao = 0.5 Å (1Å = 10-8cm)
a300 = 0.5x10-3 cm = mm Harry Kroto 2004
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Nitrosoethane Harry Kroto 2004
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What can molecules do Harry Kroto 2004
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What can molecules do 2 Harry Kroto 2004
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What can molecules do 2 Harry Kroto 2004
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