On the vibrational spectrum of methoxy. 
Methoxy has 9 vibrational degrees of freedom, 
3 totally symmetric ones (1-3), 3 doubly degenerate ones (4-6).

Because of the ^2E ground electronic state and the Jahn-Teller distortion, 
these transform to 3 times e and 3 times (a1 + a2 + e).

Overview and one quantum-chemical value (4, a2 or a1) are from 
(1) A. V. Marenich and J. E. Boggs, 
Chem. Phys. Lett. 404 (2005) 351-355;
doi: 10.1016/j.cplett.2005.01.116

Experimental values are from 
(2) P. Misra, X. Zhu, C.-Y. Hsueh, and J. B. Halpern, 
Chem. Phys. 178 (1993) 377-85;
doi: 10.1016/0301-0104(93)85077-L

(3) F. Temps, 
Adv. Ser. Phys. Chem. 4 (1995) 375-431; 
doi: 10.1142/9789812831880_0010

(4) 


all values in units of inverse centimeters with references in parentheses
(a) means that it is presently not known if it is (a1) or (a2)
* assignments taken from (4)

6(a1)  652  (3)
6(a2)  914  (3)*
3(e)  1045  (3)
6(e)  1198  (3)
5(a)  1314  (3)*
2(e)  1359  (3)*
5(a)  1403  (3)*
5(e)  1490  (3)
4(a)  2778  (3)  or 2988  (2)
4(a)  2848  (3)
1(e)  2879  (2)
4(e)  3012  (1)

we obtain in the harmonic approximation the following Qv values:

300 K: 1.08843
225 K: 1.02303
150 K: 1.00220
100 K: 1.00014
 75 K: 1.00000