BrHC=C=CH2
		Bromine
	Nuclear Quadrupole Coupling Constants
	in Bromoallene
	Bromine nuclear quadrupole coupling constants in bromoallene were determined by Ogata and Niide [1].
	Calculation of the nqcc's was made here on molecular structures given by PBE1PBE/6-31G(3d,3p) and MP2/aug-cc-pVTZ optimization, the latter with approximate equilibrium bond lengths.  These are compared with the experimental nqcc's [1] in Tables 1 and 2.  Structure parameters are given in Table 3, rotational constants in Table 4.
	In Tables 1 and 2, subscripts a,b,c refer to the principal axes of the inertia tensor; subscripts x,y,z to the principal axes of the nqcc tensor.  Ø (degrees) is the angle between its subscripted parameters.  ETA = (Xxx - Xyy)/Xzz.
	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 B1LYP/TZV(3df,3p) model for calculation of the nqcc's.
	Table 1.  79Br nqcc's in Bromoallene (MHz).  Calculation was made on the (1) PBE1PBE/6-31G(3d,3p) ropt and (2) MP2/aug-cc-pVTZ approximate re structures.     Calc. (1) Calc. (2) Expt. [1]     Xaa 384.64 384.47 377.11(94) Xbb - 108.21 - 104.76 - 97.16 Xcc - 276.44 - 279.71 - 279.95 |Xab| 375.86 379.88 381.32(24)   RMS 7.98 (3.2 %) 6.11 (2.4 %) RSD 1.58 (0.39 %) 1.58 (0.39 %)   Xxx - 311.22 - 311.97 - 306.07 Xyy - 276.44 - 279.71 - 279.95 Xzz 587.66 591.68 589.02 ETA - 0.05919 - 0.05452 - 0.04945 Øa,z 28.37 28.61 29.1 Øa,CBr 29.16 29.28 Øz,CBr   0.79   0.67
	Table 2.  81Br nqcc's in Bromoallene (MHz).  Calculation was made on the (1) PBE1PBE/6-31G(3d,3p) and (2) MP2/aug-cc-pVTZ structures.     Calc. (1) Calc. (2) Expt. [1]     Xaa 321.84 321.70 316.26(36) Xbb - 90.89 - 88.02 - 81.92 Xcc - 230.95 - 233.69 - 234.34 |Xab| 313.70 317.06 318.00(16)   RMS 6.41 (3.0 %) 4.73 (2.2 %) RSD 1.38 (0.40 %) 1.38 (0.40 %)   Xxx - 260.01 - 260.64 - 258.01 Xyy - 230.95 - 233.69 - 234.34 Xzz 490.97 494.33 492.35 ETA - 0.05919 - 0.05452 - 0.04807 Øa,z 28.33 28.57 29.0 Øa,CBr 29.12 29.24 Øz,CBr   0.79   0.67
	Table 3. Bromoallene.  Molecular structure parameters (Å and degrees).   r(1) = PBE1PBE/6-31G(3d,3p) optimization. r(2) = MP2/aug-cc-pVTZ approximate re   Point Group: Cs ropt (1) ropt (2) BrC(2) 1.8791 1.8928 HC(2) 1.0825 1.0790 C(2)C(4) 1.2990 1.3007 C(4)C(5) 1.3029 1.3059 C(5)H 1.0868 1.0822 BrC(2)H 114.28 114.41 BrC(2)C(4) 122.70 121.98 C(2)C(4)C(5) 179.51 179.82 C(4)C(5)H 121.22 120.84 HC(5)C(2)Br ±89.90 ±90.06
	Table 4.  Bromoallene.  Rotational Constants (MHz).  79Br Species.   r(1) = PBE1PBE/6-31G(3d,3p) optimization. r(2) = MP2/aug-cc-pVTZ approximate re      Calc. r(1) Calc. r(2)    Expt. [1] A 28543.2 28153.5 27849.952(63) B   2018.0   2010.0   2009.8672(40) C   1909.5   1900.6   1897.3682(27)
	[1] T.Ogata and Y.Niide, J.Chem.Soc. Faraday Trans. 88(24),3517(1992).
	Chloroallene		ClFC=C=CH2		Cyanoallene		H2C=CHBr
	Table of Contents
	Molecules/Bromine
						BrHCCCH2.html
						Last Modified 31 Dec 2011