CHF2N=C































 









Nitrogen


Nuclear Quadrupole Coupling Constants


in Difluoromethyl isocyanide


 








 








Calculation was made of the 14N nqcc tensor in difluoromethyl isocyanide on ropt structures given by B3P86/6-31G(3d,3p) and CCSD/cc-pVTZ optimization.  These calculated nqcc's are compared in Table 1 with the experimental values of Krüger et al. [1].  Structure parameters are compared in Table 2, rotational constants and dipole moments in Table 3.











In Table 1, subscripts a,b,c refer to the principal axes of the inertia tensor.  Subscripts x,y,z refer to the principal axes of the nqcc tensor.  ETA = (Xxx - Xyy)/Xzz.  Ø (degrees) is the angle between its subscripted parameters.  RMS is the root mean square difference between calculated and experimental nqcc's.  RSD is the residual standard deviation of calibration of the B3PW91/6-311+G(df,pd) model for calculation of the efg's/nqcc's.  

 








 








   







Table 1.  14N nqcc's in CHF2N=C (MHz).  Calculation was made on ropt molecular structures given by B3P86/6-31G(3d,3p) and CCSD/cc-pVTZ optimization.
   









Calc. B3P86
Calc. CCSD
Expt. [1]
   







Xaa
0.656
0.641
0.5990(10)

Xbb - 0.436 - 0.427 -
 0.4065(14)

Xcc - 0.220 - 0.214 -
 0.1926(14)

|Xac|
0.352
0.395



 







RMS
0.040 (10. %)
0.030 (7.5 %)



RSD
0.030 (1.3 %)
0.030 (1.3 %)



 







Xxx - 0.376 - 0.369



Xyy - 0.436
 - 0.427



Xzz
0.812
0.796



ETA
0.0747
0.0730



Øz,a
21.24
21.34



Øa,N=C
  9.77
  9.84



Øz,N=C
11.46
11.50



 








 

















 
 






Table 2.  CHF2N=C.  Structure parameters, B3P86/6-31G(3d,3p) and CCSD/cc-pVTZ (Å and degrees).
 








 H
 C,1,R1
 N,2,R2,1,A2
 F,2,R3,3,A3,1,D,0
 F,2,R3,3,A3,1,-D,0
 C,3,R5,2,A5,1,D1,0










   B3P86
    CCSD

 R1=1.09233577
 R2=1.40658551
 R3=1.34378221
 R5=1.17480034
 A2=110.74056484
 A3=109.36539815
 A5=176.46488944
 D=120.75908853
 D1=0.
  R1=1.08570845
 R2=1.41363022
 R3=1.33559492
 R5=1.17207123
 A2=110.40228928
 A3=109.26067438
 A5=176.72063034
 D=120.69751857
 D1=0.



 








 













Table 3.  CHF2N=C.  Rotational constants (MHz) and Dipole Mopments (D)







B3P86 CCSD   Expt [1]






A
 10086
 10181
 10110.841(42)

B
   4546
   4550
   4550.414(19)

C
   3341
   3352
   3343.550(19)






|µa|  1.32
  1.42
   1.46(1)

|µb|  0 (symm)
  0 (symm)

|µc|  1.88
   1.86
   1.83(1)



 








 








[1] M.Krüger, H.Dreizler, D.Lentz, and D.Preugschat, Z.Naturforsch. 49a,703(1994).





















CH3NC CH2FNC CF3NC (CH3)3CNC

 


















Table of Contents




Molecules/Nitrogen




 








 













CHF2NC.html






Last Modified 1 March 2014