C6H5-N=C=O





























 








Nitrogen

Nuclear Quadrupole Coupling Constants


in Phenyl Isocyanate


 








 








 








Calculation of the nitrogen nqcc's in phenyl isocyanate was made here on a structure obtained by B3LYP/6-311+G(3df,3pd) optimization.  These are compared in Table 1 with the experimental nqcc's  [1,2].  Structure parameters are given in Z-matrix format in Table 2, rotational constants in Table 3.

 








In Table 1, subscripts a,b,c refer to the principal axes of the inertia tensor; x,y,z 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 diagonal nqcc's (percentage of the average of the magnitudes of the experimental nqcc's).  RSD is the calibration residual standard deviation of the B3PW91/6-311+G(df,pd) model for calculation of the nitrogen efg's/nqcc's. 


 








 








 








Table 1. 14N nqcc's in Phenyl Isocyanate (MHz).  Calculation was made on B3LYP/6-311+G(3df,3pd) optimized structure.
 










Calc.
Expt. [1]
Expt. [2]
 








Xaa
2.738
2.701(12)
2.7241(4)

Xbb - 1.545 - 1.444(15) -
 1.4474(4)

Xcc - 1.193 - 1.258(15) -
 1.2766(4)

|Xab|
0.544














RMS


0.073 (4.0 %)
0.075 (4.1 %)

RSD
0.030 (1.3 %)














Xxx - 1.613





Xyy - 0.193





Xzz
2.806





ETA - 0.150





Øa,z
  7.13





Øa,N=C
25.29





Øz,N=C
18.16















 








 

Table 2. Phenyl Isocyanate: B3LYP/6-311+G(3df,3pd) optimized structure parameters (Å and degrees).




 C
 C,1,B1
 C,2,B2,1,A1
 C,3,B3,2,A2,1,D1,0
 C,4,B4,3,A3,2,D2,0
 C,1,B5,2,A4,3,D3,0
 H,1,B6,6,A5,5,D4,0
 H,2,B7,1,A6,6,D5,0
 H,3,B8,2,A7,1,D6,0
 H,4,B9,3,A8,2,D7,0
 H,5,B10,4,A9,3,D8,0
 N,6,B11,1,A10,2,D9,0
 C,12,B12,6,A11,1,D10,0
 O,13,B13,12,A12,6,D11,0




 B1=1.38825631
 B2=1.39010742
 B3=1.39113228
 B4=1.38732811
 B5=1.39382419
 B6=1.08053114
 B7=1.08150128
 B8=1.08105675
 B9=1.08162282
 B10=1.08163609
 B11=1.39540212
 B12=1.20028839
 B13=1.16836537
 A1=120.47902523
 A2=119.53336473
 A3=120.51562608
 A4=119.82633789
 A5=119.08709976
 A6=119.41289711
 A7=120.28910414
 A8=120.11514471
 A9=120.52591902
 A10=118.40288482
 A11=140.82126457
 A12=173.82473302
 D1=0.
 D2=0.
 D3=0.
 D4=180.
 D5=180.
 D6=180.
 D7=180.
 D8=180.
 D9=180.
 D10=180.
 D11=180.





 








 













Table 3.  Phenyl Isocyanate:  Rotational Constants (MHz).







Calc.
   Expt. [1]
  Expt. [1]






A
 5350.
 5202.103(46)
5201.7138(3)

B
   954.
   972.68072(62)
  972.68164(2)

C
   810.
   819.62766(61)
  819.62560(2)



 








 








[1] W.Kasten and H.Dreizler, Z.Naturforsch. 42a,79(1987).

[2] W.Sun, W.G.D.P.Silva, and J.van Wijngaarden, J.Phys.Chem. A, 123(12),2351(2019).

 








 








C6H5N=C=S
 HN=C=O
 CH3N=C=O
 (CH3)3CN=C=O










 








Table of Contents




Molecules/Nitrogen




 








 













C6H5NCO.html






Last Modified 16 March 2019