SiF2

Rotational and centrifugal distortion (28Si19F2)

Watson's
Determinable
Parameters
Value a
[MHz]
Derived Parameters
(assuming planarity conditions)
Value a
[MHz]
Ref.
A 30 602.2556(507) A 30 602.241(51) 72031
B 8823.4827(146) B 8823.517(14)
C 6830.2589(158) C 6830.356(17)
τ1 0.234 713(12 794) τbbcc -0.0285(10)
τ2 0.023 005(2522) τccaa 0.0692(31)
τ3 b 0.383(39) τaabb 0.1940(94)
τaaaa -1.992 13(655) τaabb (1) 0.2813(47)
τbbbb -0.070 847 3(13 806) τaabb (2) 0.2612(67)
τcccc -0.014 864(732) τaabb (3) 0.2612(67)
HJ -0.352 510 ± 0.164 x 10-5 τabab (1) -0. 0436(36)
HJK -0.598 708 ± 0.268 x 10-4 τabab (2) -0.0269(66)
HKJ -0.406 91 ± 0.162 x 10-4 τabab (3) -0.0234(75)
HK -0.3145 ± 0.320 x 10-4 Δτ -0.119(37) x 10-2
hJ c -0.147 07 ± 0.057 x 10-5  
hJK -0.20654 ± 0.116 x 10-4
hK 0.8732 ± 0.392 x 10-4
Std. dev. 0.151
No. lines fit 73

a The uncertainties quoted are one standared deviation as estimated by the least squares fit. The number of significant figures quoted are necessary to reproduce the calculated transition frequencies within their standard deviations.

b Strictly speaking, τ3 is not a determinable parameter, but is calculated from τ1, τ2, τaaaa, and τbbbb using the planarity conditions.

c Watson uses 2hJ for this parameter.

Rotational constants and electric dipole moment for SiF2

Isotopic
Species
Vib. State
υ1 υ2 υ3
A
[MHz]
B
[MHz]
C
[MHz]
Ref.
28Si19F2 0   0   0 a a a   
1   0   0 b 30 651.64(17) 8768.17(6) 6797.70(90) 73036
0   1   0 31 054.31(4) 8807.71(3) 6808.23(1) 66021
0   0   1 b 30 300.85(13) 8809.96(5) 6806.57(90) 73036
29Si19F2 0   0   0 29 994.39(37) 8823.77(5) 6799.63(14) 66021
30Si19F2 0   0   0 29 428.3 8824.0 6770.2
Electric dipole moment
28Si19F2 µb [C · m]
     µb [D]
4.103(50) x 10-30 
     1.230(15)
65012

a See ground state constants.

b The intervibration-state transition, υ1 = 1, 854 ← υ3 = 1, 817, has ben measured at 54 351.8(1) MHz [73036]. Due to format difficulties, this is not shown in the microwave spectrum of 28Si19F2.

Additional reference [66020].


NIST Physical Measurement Laboratory National Institute of Standards and Technology NIST Physical Measurement Laboratory Back to the triatomic molecule selection page