C3H2   -   Cyclopropenylidene

Molecular constants for cyclopropenylideneazulene (HCCCH)
Parameter Value Ref. Parameter Value Ref.
A″ [MHz] 35 092.5923(56) a b A [MHz] 35 092.6121(18) c 86008
B″ [MHz] 32 212.9250(56) B [MHz] 32 212.7811(18)
C″ [MHz] 16 749.3081(56) C [MHz] 16 749.1067(18)
τ1 [MHz] -0.6762(14) DJ [MHz] 0.020 307(37)
τ2 [MHz] -0.162 77(46) DJK [MHz] 0.172 0642(25)
τ3 [MHz] 17.314(14) DK [MHz] -0.044 8652(41)
τaaaa [MHz] -0.590 28(46) d1 [MHz] -0.016 3698(14)
τbbbb [MHz] -0.298 21(46) d2 [MHz] -0.010 705 97(70)
τcccc [MHz] -0.035 48(48)  
HJ [Hz] 0 d   0 d
HJK [Hz] 4.388(17)   3.2560(22)
HKJ [Hz] -11.747(110)   -9.359(16)
HK [Hz] 8.716(101)   7.288(28)
hJ [Hz] 0.609(26) h1 [Hz] 0 d
hJK [Hz] 0 d h2 [Hz] 0.161 44(68)
hK [Hz] 0.461(57) h3 [Hz] 0 d
  LJK [Hz] -0.000 126(19)
LJK [Hz] 0.000 292(38)
σ e 1.4 σ f 19.2
Electric Dipole Moment
µb [C · m]
    µb [D]		 11.07(17) x 10-30 
    3.32(5)		 87011  
µb [C · m]
    µb [D]		 11.44(7)x 10-30 
    3.43(2)		 87022
 
a Two standard deviations.
 
b J. Phys. Chem. Ref. Data 18(3), 1245-1524. (1989). 
 
c One standard deviation.		  
d These constants were poorly determined and set to zero.
 
e Weighted fit. This gives a standard deviation of about 30 kHz.
 
f Unweighted fit.

 

 

Molecular constants for cyclopropenylidene and its monosubstituted derivatives
Parameter C3H2 13C on-axix 13C off-axix C3HD Ref.
A [MHz] 35 092.5083(32) a 33 310.5202(50) 34 857.1875(25) 34 517.5188(16) 87004
B [MHz] 32 212.9468(32) 32 212.5804(43) 31 288.4887(24) 26 965.8135(15)
C [MHz] 16 749.0286(32) 16 331.2875(27) 16 443.0399(22) 15 098.4567(12)
ΔJ [kHz] 41.689(65) 41.482(45) 40.338(35) 30.892(13)
ΔJK [kHz] 44.017(55) 36.618(89) 38.941(26) 51.623(20)
ΔK [kHz] 61.871(38) 53.679(99) 65.734(21) 61.068(24)
δJ [kHz] 16.4338(86) 16.5134(81) 15.9455(40) 12.0039(38)
δK [kHz] 58.610(20) 53.155(20) 56.422(10) 60.265(11)
HJ [kHz] 0 b 0 b 0 b 0 b
HJK [kHz] 6.37(84) 5.53(26) 5.268(18) 2.405(44)
HKJ [kHz] -14.7(12) -14.32(49) -11.019(28) -4.39(16)
HK [kHz] 10.08(56) 9.94(30) 7.319(44) 2.66(20)
hJ [kHz] 0.477(75) 0.477 c 0.477 c 0.2225(73)
hJK [kHz] -0.88(37) -0.88 c -0.88 c -0.88 c
hK [kHz] 1.22(31) 1.22 c 1.22 c 3.706(88)
σ [kHz] 34.1 d 37.6 d 26.7 d 28.3 d
eQqaa [kHz]   180.9(13) 87016
eQqcc [kHz] -87.5(18)
 
a The numbers in parentheses denote one standard deviation in the last quoted digits.
 
b This constant was set equal to zero.
 
c These constants were constrained to the values obtained for the parent species.
 
d Standard deviation of the fit.

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