C4H2   -   Butadiyne

Molecular constants for 1,3-butadiyne (diacetylene) in excited vibrational states

Parameter Upper State a Lower State a Ref.
ν8 - ν6 band ν8 ν6  
Bυ [MHz] 4391.1921(94) 4391.3230(84) 81046
Dυ [kHz] 0.594(179) 0.582(154)
qυ [MHz] 2.4073(37) 2.4830(32)
ΔGυ [MHz] 71 868.336(57)
µb [C · m]
    µb [D]
0.2625(33) x 10-30
     0.0787(10)
Σg+ - Σu+ subband ν8 + ν9 (g) ν6 + ν9 (u)  
Bυ [MHz] 4402.9090(61) 4403.8625(56) 82036
Dυ [kHz] 0.854(54) 1.826(47)
Hυ [Hz] -0.118(155) 0.003(121)
ΔGυ [MHz] 46112.301(42)
µb [C · m]
    µb [D]
0.2518(17) x 10-30
    0.0755(5)
Σg- - Σu- subband
Bυ [MHz] 4403.7414(36) 4403.8795(41)
Dυ [kHz] 0.713(37) 0.767(43)
Hυ [Hz] 0.243(207) 0.212(179)
ΔGυ [MHz] 73 412.284(29)
µb [C · m]
    µb [D]
0.2685(13)  x 10-30
    0.0805(4)
Δg - Δu subband
Bυ [MHz] 4403.7192(56) 4403.8715(64)
Dυ [kHz] 0.302(49) -0.216(56)
Hυ [Hz] 0.425(229) 0.296(201)
ρυ [Hz] 0.0492(134) 0.5185(128)
ρυ [Hz] 0.320(68) 0.212(57)
ΔGυ [MHz] 77 573.622(58)
 
a Values in parentheses denote 2.5 σ uncertainties.

 

 

Molecular constants for HC≡CC≡CD

State B [MHz] D [kHz] q [MHz] µ [C · m] µ [D] Ref.
ν6 (Π) 4086. 2165(44) a 0.408(36) 2.1316(28) 0.3025(20) x 10-30 0.0907(6) 81047
2ν6 (Δ) 4087.6963(58) 0.349(50)   0.5607(47) x 10-30 0.1681(14)
ν6 + ν9 (Δ) 4097.7537(50) 0.358(44) 0.3002(13) x 10-30 0.0900(4)
2ν8 (Δ) 4094.4786(103) 0.351(85)    
ν6 + ν7 (Δ) 4092.9074(176) 1.419(145)
ν7 + ν8 (Δ) 4095.8925(354) 0.355(290)
2ν6 + ν9 (φ) 4098.9505(339) 0.372(303)
Ground b 4084.74   0.0444 x 10-30 0.0133
 
a The 2.5 σ uncertainties are given in parentheses for the last digits shown.
 
b Extrapolated from the ν6 and 2ν6 state values.

 

 

Molecular constants for 1,3-butadiyne (diacetylene-d) in excited vibrational states

Parameter Upper State a Lower State a Ref.
ν6 - ν8 band ν6 ν8  
Bυ [MHz] 3814.2822(15) 3812.9142 84037
Dυ [kHz] 0.3113(128) 0.3149(113)
qυ [MHz] 2.2874(17) 2.2767(15)
ΔGυ [MHz] 86 417.951(13)
µ [C · m]
    µ [D]
0.1501(37) x 10-30
    0.0450(11)
  ν6 + ν9 (u) ν8 + ν9 (g)
Bυ [MHz] Σ+ 3824.3631(43) 3823.0200(44)
  Σ- 3824.4347(40) 3823.0598(43)
  Δ 3824.3726(33) 3823.0410(36)
Dυ [kHz] Σ+ 0.3439(731) 0.3469(674)
  Σ- 0.3493(388) 0.3519(381)
  Δ   0.3182(283) 0.3197(278)
δG [MHz] Δ - Σ+ 27 847.(681) 53 389.(681)
  Δ - Σ- 32 184.(2242) 30 382.(2242)
ΔG [MHz] Σ+ 111 358.561(38)  
  Σ- 84 014.468(35)
  Δ   85 816.240(33)
q9 [MHz] 4.898(240)
q6 [MHz] 2.2874 fixed
q8 [MHz] 2.2767 fixed
 
a Values in parentheses denote 2.5 σ uncertainties.


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