With the B3LYP calculation method of density functional theory（DFT）and the 6-31G＊ basis set,full optimization calculation was made for phenoxathiin10-oxide（PTO）and 135 polybromine phenoxathiin 10-oxides（PBPTOs）...With the B3LYP calculation method of density functional theory（DFT）and the 6-31G＊ basis set,full optimization calculation was made for phenoxathiin10-oxide（PTO）and 135 polybromine phenoxathiin 10-oxides（PBPTOs）with the Gaussian 03 program and molar heat capacity in constant volume（CVθ）value of each molecule in the standard state was obtained.The relation between CVθ and the substitution position and number of bromine atom（NPBS）was studied,and the results indicated good correlation（R2 = 1.000）between CVθ and NPBS of PBPTO compounds.Based on the output file of Gaussian 03 program,molar heat capacity at constant pressure（Cp,m）of PBPTO compounds from 200 to 1,000 K was calculated with the statistical thermodynamics program,and the correlation equation between Cp,m and temperature（T,T-1 and T-2）was obtained with the least-squares method,and the correlation coefficient of the correlation equation（R2）was 1.000.In addition,based on the partition function of each molecule calculated by vibration analysis,the relative rate constant of formation of each molecule was calculated.展开更多
Decabromodiphenyl ether （BDE-209）, the major congener in the high volume industrial flame retardant mixture ＂DecaBDE＂, has become a ubiquitous environmental contaminant. In the present work, combined experimental ...Decabromodiphenyl ether （BDE-209）, the major congener in the high volume industrial flame retardant mixture ＂DecaBDE＂, has become a ubiquitous environmental contaminant. In the present work, combined experimental and theoretical studies have been undertaken on the structure and vibrational spectra of BDE-209. The FT-IR （400-4000 cm-1） and FT-Raman spectra （100-4000cm-1） of BDE-209 were recorded, while density functional B3LYP calculations were employed in conjunction with the 6-31G（d） basis set for investigating the corresponding geometric structure and vibrational spectroscopic properties. Besides, the detailed interpretations of fundamental vibrations were performed on the basis of experimental results and potential energy distribution （PED） of the vibrational modes. Optimized structures of the title compound were interpreted and compared with the earlier reported experimental values, which yield good agreement. Finally, the measured and calculated harmonic vibrational wavenumbers were compared with each other, and they were found to be in good accordance.展开更多
China has experienced rapid economic development and industrialization during the past four decades,leading to widespread distribution of various types of industrial facilities[1].With the understanding of soil contam...China has experienced rapid economic development and industrialization during the past four decades,leading to widespread distribution of various types of industrial facilities[1].With the understanding of soil contamination induced by industrial sites and rapid urbanization,abandoned industrial sites are generally reclassified for urban land[2].The remained brownfield sites(the sites of abandoned,idle,or under used industrial and commercial facilities where expansion or redevelopment is hindered by environmental contamination)exhibit great health risks to the residents due to that pollutants were continuously discharged intothe surrounding environments[3].展开更多
基金supported by the National Natural Science Foundation of China (41071319,20977046 and 20737001)
文摘With the B3LYP calculation method of density functional theory（DFT）and the 6-31G＊ basis set,full optimization calculation was made for phenoxathiin10-oxide（PTO）and 135 polybromine phenoxathiin 10-oxides（PBPTOs）with the Gaussian 03 program and molar heat capacity in constant volume（CVθ）value of each molecule in the standard state was obtained.The relation between CVθ and the substitution position and number of bromine atom（NPBS）was studied,and the results indicated good correlation（R2 = 1.000）between CVθ and NPBS of PBPTO compounds.Based on the output file of Gaussian 03 program,molar heat capacity at constant pressure（Cp,m）of PBPTO compounds from 200 to 1,000 K was calculated with the statistical thermodynamics program,and the correlation equation between Cp,m and temperature（T,T-1 and T-2）was obtained with the least-squares method,and the correlation coefficient of the correlation equation（R2）was 1.000.In addition,based on the partition function of each molecule calculated by vibration analysis,the relative rate constant of formation of each molecule was calculated.
基金financially supported by the National Natural Science Foundation of China(41071319,20977046)the Fundamental Research Funds for the Central Universities of China(1112021101)
文摘Decabromodiphenyl ether （BDE-209）, the major congener in the high volume industrial flame retardant mixture ＂DecaBDE＂, has become a ubiquitous environmental contaminant. In the present work, combined experimental and theoretical studies have been undertaken on the structure and vibrational spectra of BDE-209. The FT-IR （400-4000 cm-1） and FT-Raman spectra （100-4000cm-1） of BDE-209 were recorded, while density functional B3LYP calculations were employed in conjunction with the 6-31G（d） basis set for investigating the corresponding geometric structure and vibrational spectroscopic properties. Besides, the detailed interpretations of fundamental vibrations were performed on the basis of experimental results and potential energy distribution （PED） of the vibrational modes. Optimized structures of the title compound were interpreted and compared with the earlier reported experimental values, which yield good agreement. Finally, the measured and calculated harmonic vibrational wavenumbers were compared with each other, and they were found to be in good accordance.
基金supported by the National Key Research and Development Program of China(2020YFC1806700)the National Natural Science Foundation of China(42230505 and 42206148)。
文摘China has experienced rapid economic development and industrialization during the past four decades,leading to widespread distribution of various types of industrial facilities[1].With the understanding of soil contamination induced by industrial sites and rapid urbanization,abandoned industrial sites are generally reclassified for urban land[2].The remained brownfield sites(the sites of abandoned,idle,or under used industrial and commercial facilities where expansion or redevelopment is hindered by environmental contamination)exhibit great health risks to the residents due to that pollutants were continuously discharged intothe surrounding environments[3].
