CH2BrI
		Bromine and Iodine
	Nuclear Quadrupole Coupling Constants
		in Bromoiodomethane
	The complete 79Br, 81Br, and 127I nqcc tensors in bromoiodomethane were determined by Bailleux, et al. [1] - as well as an ropt structure given by CCSD(T) with aug-cc-pVTZ bases on C and H, and cc-pVTZ-PP bases on Br and I; and a partial ground state effective ro structure.
	Calculation of the bromine and iodine nqcc's was made here on these ropt and ro structures.  These calculated nqcc's are compared with the experimental values [1] in Tables 1 - 3.  Structure parameters are given in Table 4.
	In Tables 1 - 3, 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 for the B1LYP/TZV(3df,3p) (with TZVPPall on I) model for calculation of the bromine efg's/nqcc's, and of the B1LYP/6-311G(df,p) model for the iodine efg's/nqcc's.
	Subscripts a,b,c refer to the principal axes of the inertia tensor; x,y,z to the principal axes of the nqcc tensor.  The nqcc y-axis is chosen coincident with the inertia c-axis, these are perpendicular to the molecular symmetry plane.  ETA = (Xxx - Xyy)/Xzz.  Ø (degrees) is the angle between its subscripted parameters.
	Table 1. 79Br nqcc's in CH2BrI (MHz).  Calculation was made on ropt and partial ro molecular structures.     Calc /ropt Calc /ro Expt. [1]     79Br Xaa 315.62 311.58 304.3803(11) Xbb   - 6.23   - 2.47     4.3527(12) Xcc - 309.39 - 309.11 - 308.7331(17) |Xab| 415.75 416.38 418.0130(52)   RMS 8.80 (4.3 %) 5.73 (2.8 %) RSD 1.58 (0.4 %) 1.58 (0.4 %)   Xxx - 291.11 - 290.44 - 289.7495(49) Xyy - 309.39 - 309.11 - 308.7331(17) Xzz 600.50 599.55 598.4825(49) ETA 0.0304 0.0311 0.0317 Øz,a 34.42 34.67 35.13 Øa,CBr 35.75 36.01 Øz,CBr   1.33   1.34
	Table 2. 127I nqcc's in CH279BrI (MHz).  Calculation was made on ropt and partial ro molecular structures.     Calc /ropt Calc /ro Expt. [1]     127I Xaa - 1304.8 - 1288.4 - 1275.3137(13) Xbb   262.1   232.7   236.3851(12) Xcc 1042.7 1055.7 1038.9286(18) |Xab| 1284.6 1331.9 1296.1970(44)   RMS 22.7 (2.7 %) 12.5 (1.5 %) RSD 15.2 (1.2 %) 15.2 (1.2 %)   Xxx   983.3 1005.9   981.0140(39) Xyy 1042.7 1055.7 1038.9286(18) Xzz - 2026.1 - 2061.6 - 2019.9426(39) ETA 0.0293 0.0242 0.0287 Øz,a 29.31 30.14 29.88 Øa,CI 30.29 30.46 Øz,CI   0.98   0.32
	Table 3. 81Br and 127I nqcc's in CH281BrI (MHz).  Calculation was made on ropt and partial ro molecular structures..     Calc /ropt Calc /ro Expt. [1]     81Br Xaa 264.23 260.87 254.8259(12) Xbb   - 5.74   - 2.61     3.0841(12) Xcc - 258.49 - 258.26 - 257.9100(17) |Xab| 347.49 347.66 348.9990(97)   RMS 7.45 (4.3 %) 4.80 (2.8 %) RSD 1.38 (0.4 %) 1.38 (0.4 %)   127I Xaa - 1302.8 - 1286.3 - 1273.2494(13) Xbb   260.1   230.6   234.3227(12) Xcc 1042.7 1055.7 1038.9267(17) |Xab| 1285.9 1333.1 1297.3694(69)   RMS 22.8 (2.7 %) 12.5 (1.5 %) RSD 15.2 (1.2 %) 15.2 (1.2 %)
	Table 4.  CH2BrI Molecular structure parameters, CCSD(T) ropt and partial ro (Å and degrees).  For the  ro structure, quantities in brackets - taken from the ropt structure - are assumed.     ropt    ro CH 1.0830 [1.0830] CBr 1.9264  1.9261 CI 2.1313 [2.1313] HCH 111.95  107.66 BrCI 113.96  113.53 BrCH 107.99  107.27
	[1] S.Bailleux, D.Duflot, K.Taniguchi, S.Sakai, H.Ozeki, T.Okabayashi, and W.C.Bailey, J.Phys.Chem. A, 118,11744(2014).
	CH2BrF		CH2BrCl		CH2Br2		CH2FI
	CH2ClI		CH2I2
	Table of Contents
	Molecules/Bromine
	Molecules/Iodine
						CH2BrI.html
						Last Modified 12 Oct 2014