C2H2   -   Acetylene

Molecular constants for d1-acetylene (HCCD)
Parameter Ground State Ref. ν4 ν5 Ref.
B0 [MHz] 29 725.24(5) 69062 29 803.003(6) 29 766.750(4) 80037
D0 [MHz] 0.0336(32)    
Dc [MHz]     0.0363(9) 0.0342(2) 80037
Dd [MHz] 0.0303(12) 0.0352(3)
qυ [MHz] 132.993(14) 105.702(8)
µυ [C · m]
     µ υ [D]		 0.078 69(17) x 10-30 
     0.023 59(5)		 0.186 83(30) x 10-30 
     0.056 01(9)
  3ν4 (Π) 3ν5 (Π)    
Bυ [MHz]     29 969.052(43) 29 861.189(27) 80037
Dc [MHz]     0.0402(9)
Dd [MHz]     0.0450(12)
qυ [MHz] 135.529(25) 108.642(28)
µυ [C · m]
     µ υ [D]		 0.300 46(9) x 10-30 
     0.090 077(26)		 0.4910(70) x 10-30 
     0.1472(21)

 

   

Molecular constants for DCCD from the ν51 - ν41 band
Parameter Value Ref.
ν0 (cm-1) 27.104 61(19) 77038
B4 [MHz] 25 480.70(43)
B5 [MHz] 25 483.24(46)
D4 [MHz] 0.024 36(19)
D5 [MHz] 0.024 27(23)
q4 [MHz] 97.02(18)
q5 [MHz] 98.02(22)
ν4 [MHz] 0.000 23(17)
ν5 [MHz] 0.000 13(21)
B5 - B4 [MHz] 2.537(34)
q5 - q4 [MHz] 0.992(16)
D5 - D4 [MHz] -0.000 083(49)
Deuterium hyperfine constants
eQq (ν4) [MHz] 0.209 16 87023
eQq (ν5) [MHz] 0.208 70
c (ν4) [MHz] -0.44 x 10-3
c (ν5) [MHz] -0.40 x 10-3

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