Vibrational frequencies and structural determinations of maleonitrile

The vibrational frequencies and corresponding normal mode assignments of maleonitrile are examined theoretically using the GAUSSIAN98 set of quantum chemistry codes. All normal modes were successfully assigned to one of eight types of motion predicted by a group theoretical analysis (C triple bond N stretch, C=C stretch, C-C stretch, C-H stretch, C-H bend, C-C triple bond N bend, C-C triple bond N bend, C-C=C-C torsion) utilizing the C(2v) symmetry of the molecule. The molecular orbitals of maleonitrile are also examined.     

Vibrational frequencies and structural determinations of tetraisocyanatosilane

The normal mode frequencies and corresponding vibrational assignments of Si(NCO)(4) are examined theoretically using the GAUSSIAN 98 set of quantum chemistry codes. Each of the vibrational modes was assigned to one of six types of motion predicted by a group theoretical analysis (Si-N stretch, N-C-O symmetric stretch, N-C-O asymmetric stretch, N-C-O bend, Si-N-C bend, and N-Si-N bend) utilizing the T(d) symmetry of the molecule. Uniform scaling factors were derived for each type of motion. Predicted infrared and Raman intensities are reported.     

Vibrational frequencies and structural determinations of urazole

The vibrational frequencies and corresponding normal mode assignments of urazole are examined theoretically using the Gaussian98 set of quantum chemistry codes. All normal modes were successfully assigned to one of eight types of motion (N--H stretch, C=O stretch, C--N stretch, N--N stretch, N--H bend, C=O bend, N--C--N bend, ring torsion) utilizing the C2 symmetry of the molecule. The molecular orbitals of urazole are examined. The simultaneous double inversion of the amine groups in urazole is also examined.     

Vibrational frequencies and structural determination of cyanogen azide

The vibrational frequencies and corresponding normal mode assignments of cyanogen azide are examined theoretically using the Gaussian03 set of quantum chemistry codes. All normal modes were successfully assigned to one of seven types of motion predicted by a group theoretical analysis (NN stretch, NN stretch, N–C stretch, CN stretch, NNN bend, NN–C bend, and N–CN bend). Theoretical infrared and Raman intensities are reported. The molecular orbitals and bonding of cyanogen azide are examined.     

Vibrational frequencies and structural determination of 1,6-dicarba-closo-hexaborane(6)

The normal mode frequencies and corresponding vibrational assignments of 1,6-dicarba-closo-hexaborane(6) are examined theoretically using the GAUSSIAN98 set of quantum chemistry codes. All normal modes were successfully assigned to one of six types of motion predicted by a group theoretical analysis (B-B stretch, B-C stretch, B-H stretch, C-H stretch, B-H bend, and C-H bend) utilizing the D(4h) symmetry of the molecule. The vibrational modes of the naturally isotopically substituted (1-(10)B, 2-(10)B 3-(10)B, and 4-(10)B) forms of 1,6-dicarba-closo-hexaborane(6) were also calculated and compared against experimental data. A complex pattern of frequency shifts and splittings is revealed.     

Vibrational frequencies and structural determination of aluminum tetrahydroborate

The normal mode frequencies and corresponding vibrational assignments of aluminum tetrahydroborate in D3 symmetry are examined theoretically using the 98 set of quantum chemistry codes. All normal modes were successfully assigned to one of seven types of motion (B-H stretch, Al-B stretch, B-Al-B bend, H-B-H bend, BH4 wag, BH4 rock, and BH4 twist) predicted by a group theoretical analysis. By comparing the vibrational frequencies with infrared and Raman spectra available in the literature, a set of scaling factors is derived. Theoretical infrared intensities and Raman activities are reported.     

Vibrational frequencies and structural determination of tetraethynylstannane

The normal mode frequencies and corresponding vibrational assignments of Sn(CCH)₄ are examined theoretically using the 98 set of quantum chemistry codes. Each of the vibrational modes was assigned to one of six types of motion predicted by a group theoretical analysis (Sn–C stretch, CC stretch, C–H stretch, CC–H bend, Sn–CC bend, and C–Sn–C bend) utilizing the T_d symmetry of the molecule. A set of uniform scaling factors were derived for each type of motion. Predicted infrared and Raman intensities are reported.     

Vibrational frequencies and structure determination of silylgermane

The normal mode frequencies and corresponding vibrational assignments of silylgermane are examined theoretically using the GAUSSIAN 98 set of quantum chemistry codes. All normal modes were successfully assigned to one of seven types of motion predicted by a group theoretical analysis (Si-H stretch, Ge-H stretch, Si-Ge stretch, H-Si-H bend, H-Ge-H bend, SiH(3) wag/GeH(3) wag and Si-Ge torsion) utilizing the C(3v) symmetry of the molecule. Predicted infrared and Raman intensities are presented. Molecular orbitals are presented and bonding is examined in terms of the molecular orbitals.     

Vibrational frequencies and structural determinations of tetraisocyanatogermane

The normal mode frequencies and corresponding vibrational assignments of Ge(NCO)₄ are examined theoretically using the 98 set of quantum chemistry codes. Each of the vibrational modes was assigned to one of six types of motion predicted by a group theoretical analysis (Ge–N stretch, N–C–O symmetric stretch, N–C–O asymmetric stretch, N–C–O bend, Ge–N–C bend, and N–Ge–N bend) utilizing the T_d symmetry of the molecule. Uniform scaling factors were derived for each type of motion. Predicted infrared and Raman intensities are reported.     

Vibrational frequencies and structural determinations of 1,1-dicyanocyclopropane

The vibrational frequencies and corresponding normal mode assignments of 1,1-dicyanocyclopropane are examined theoretically using the Gaussian98 set of quantum chemistry codes. All normal modes were successfully assigned to one nine types of motion predicted by a group theoretical analysis (C-H stretch, C[triple bond]N stretch, C-C stretch, C-C[triple bond]N bend, C-C-C bend, CH2 scissors, CH2 wag, CH2 rock, CH2 twist) utilizing the C2v symmetry of the molecule. The molecular orbitals of 1,1-dicyanocyclopropane are also examined.     

Vibrational frequencies and structural determination of trimethylarsine oxide

The normal mode frequencies and corresponding vibrational assignments of trimethylarsine oxide are examined theoretically using the Gaussian 98 set of quantum chemistry codes. All normal modes were successfully assigned to one of eight types of motion (As-C stretch, As=O stretch, C-H stretch, C-As-C bend, As=O bend, H-C-H bend, CH3 wag, and CH3 twist) utilizing the C3v symmetry of the molecule. Calculations were performed at the Hartree-Fock, DFT(B3LYP), and MP2 levels of theory using the standard 6-311G** basis. Calculated infrared intensities and Raman activities are reported.     

Vibrational frequencies and structural determination of dicyanodifluorosulfur

The normal mode frequencies and corresponding vibrational assignments of dicyanodifluorosulfur are examined theoretically using the Gaussian03 set of quantum chemistry codes. Each of the vibrational modes was assigned to one of six types of motion predicted by a group theoretical analysis (CN stretch, SC stretch, SF stretch, FSC bend, SCN bend, and CSC bend) utilizing the C(2v) symmetry of the molecule. A set of uniform scaling factors was derived for each type of motion. Predicted infrared and Raman intensities are reported.     

Vibrational frequencies and structural determinations of tert-butylacetylene

The normal mode frequencies and corresponding vibrational assignments of tert-butylacetylene (TBA) are examined theoretically using the Gaussian 98 set of quantum chemistry codes. All normal modes were successfully assigned to one of the nine types of motion (C---C stretch, CC stretch, C---H stretch, C---C---C bend, CC---C bend, CC---H bend, H---C---H bend, CH₃ rock, and CH₃ twist) utilizing the C_3v symmetry of the molecule. Calculations were performed at the Hartree–Fock, B3LYP, and MP2 levels of theory using the standard 6-311G^** basis. Theoretical results were successfully compared against available experimental data.     

Vibrational frequencies and structural determination of Al(8)S(12)

The normal mode frequencies and corresponding vibrational assignments of Al(8)S(12) in T(h) symmetry are examined theoretically using the Gaussian98 set of quantum chemistry codes. All normal modes were successfully assigned to one of four types of motion (Al-S stretch, Al-S-Al bend, S-Al-S bend, and Al-S-Al wag) predicted by a group theoretical analysis. Normal mode frequencies are predicted and calculated infrared intensities and Raman activities are presented. The thermodynamics of the reaction 2Al(4)S(6)-->Al(8)S(12) are examined.     

Vibrational frequencies and structural determination of triethynylmethylsilane

The normal mode frequencies and corresponding vibrational assignments of Triethynylmethylsilane (CH3Si(CCH)3) are examined theoretically using the Gaussian98 set of quantum chemistry codes. Each of the vibrational modes was assigned to one of nine types of motion predicted by a group theoretical analysis (Si-C stretch, C triple bond C stretch, C-H stretch, C triple bond C-H bend, Si-C triple bond C bend, C-Si-C bend, H-C-H bend, CH3 wag, and CH3 twist) utilizing the C3v symmetry of the molecule. A set of uniform scaling factors was derived for each type of motion. Predicted infrared and Raman intensities are reported.     

Vibrational frequencies and structural determination of hafnium tetrahydroborate

The normal mode frequencies and corresponding vibrational assignments of of hafnium tetrahydroborate in T symmetry are examined theoretically using the Gaussian 98 set of quantum chemistry codes. All normal modes were successfully assigned to one of to one of six types of motion (B-H stretch, Hf-B stretch, B-Hf-B bend, H-B-H bend, BH4 wag, and BH4 twist) predicted by a group theoretical analysis. By comparing the vibrational frequencies with IR and Raman spectra available in the literature, a set of scaling factors is derived. Theoretical IR and Raman intensities are reported. Quantum chemical calculations predict that the molecule does not possess strict Td symmetry. The Td structure possesses one negative eigenvalue. The minimum energy structure possesses T symmetry.     

Vibrational frequencies and structural determination of 1,3-dichloro-1,3-diazetidine-2,4-dione

The normal mode frequencies and corresponding vibrational assignments of 1,3-dichloro-1,3-diazetidine-2,4-dione are examined theoretically using the Gaussian 98 set of quantum chemistry codes. Each of the vibrational modes was assigned to one of six types of motion predicted by a group theoretical analysis (C=O stretch, N-C stretch, N-Cl stretch, N-C-N bend, N-Cl bend, and C=O bend) utilizing the C2h symmetry of the molecule. Uniform scaling factors was derived for each type of motion. Predicted infrared and Raman intensities are reported.     

Vibrational frequencies and structural determination of trichloroboroxine

The normal mode frequencies and corresponding vibrational assignments of trichloroboroxine (B3O3Cl3) in D3h symmetry are examined theoretically using the Gaussian 98 set of quantum chemistry codes. All normal modes were successfully assigned to one of five types of motion (B-Cl stretch, B-O stretch, B-Cl bend, O-B-O bend, and B(OOCl) umbrella motion) predicted by a group theoretical analysis. By comparing the vibrational frequencies with IR and Raman spectra available in the literature, a set of scaling factors is derived. Molecular orbitals and bonding are examined.     

Vibrational frequencies and structural determination of triethynylmethylstannane

The normal mode frequencies and corresponding vibrational assignments of Triethynylmethylstannane (SnCH(3)(CCH)(3)) are examined theoretically using the Gaussian 98 set of quantum chemistry codes. Each of the vibrational modes was assigned to one of nine types of motion predicted by a group theoretical analysis (Sn-C stretch, C[triple bond]C stretch, C-H stretch, C[triple bond]C-H bend, Sn-C[triple bond]C bend, C-Sn-C bend, H-C-H bend, CH(3) wag, and CH(3) twist) utilizing the C(3v) symmetry of the molecule. A set of uniform scaling factors was derived for each type of motion. Predicted infrared and Raman intensities are reported.     

Vibrational frequencies and structural determination of diethynyldimethylsilane

The normal mode frequencies and corresponding vibrational assignments of diethynyldimethylsilane are examined theoretically using the Gaussian 98 set of quantum chemistry codes. Each of the vibrational modes was assigned to one of nine types of motion predicted by a group theoretical analysis (Si-C stretch, C[triple bond]C stretch, C-H stretch, C[triple bond]C-H bend, Si-C[triple bond]C bend, C-Si-C bend, H-C-H bend, CH3 wag, and CH3 twist) utilizing the C3v symmetry of the molecule. A set of uniform scaling factors was derived for each type of motion. Predicted infrared and Raman intensities are reported.