Abstract
The $ν_a+amide II$ combination band of thiopropionamide has been recorded for investigation of Hydrogen bonding between thiopropionamide (TPA) and N,N-dimethylalkylamide (DMF, DMA and DMP) in carbon tetrachloride over the range of $5^{\circ}$ to $55^{\circ}$. The combination band of monomeric TPA and hydrogen-bonded TPA can be resolved by Lorentzian-Gaussian product function into monomeric TPA and hydrogen-bonded TPA with amides. The association constants ($K_1$) for the hydrogen-bonded TPA were calculated by the concentrations of the monomeric TPA and the hydrogen-bonded TPA obtained from the computer resolved absorption bands. Thermodynamic parameters for the Hydrogen bonding have been evaluated by the analysis of the temperature dependent spectra. The ${\Delta}$$H^{\circ}$ of hydrogen-bonded TPA with DMF, DMA and DMP have been found to be-12.5, -13.5 and -14.1 kJ/mol, respectively. The corresponding ${\Delta}$$S^{\circ}$for the above system were -15.2, -17.9 and -22.3 J/mol${\cdot}$deg, respectively.
사염화탄소 용액중에서 thiopropionamide(TPA)와 N,N-dimethylalkylamides(DMF, DMA, DMP)간의 수소결합에 관한 열역학적 상수를 구하기 위하여 TPA의 근적외선 영역의 흡수띠 중에서 $ν_a+amide II$조합띠를 사용하여 5${\sim}$55$^{\circ}C$ 범위에서 실험하였다. TPA 단위체와 수소결합을 하고 있는 TPA의 혼합 흡수띠를 Lorentzian-Gaussian product function을 사용하여 개개의 띠로 분리하였다. 컴퓨터로 분해하여 얻은 개개의 흡수띠의 면적을 사용하여 단위체 및 1 : 1 복합체의 농도를 계산하였고 이로부터 평형상수를 구하였다. 열역학적 상수들은 온도의존 흡수띠를 분석하여 구하였다. TPA와 DMF, DMA 및 DMP간의 1 : 1 복합체의 ${\Delta}$$H^{\circ}$는 각각 -12.5, -13.5, -14.1kJ/mol이었고.${\Delta}$$S^{\circ}$는 각각 -15.2, -17.9, -22.3kJ/mol${\cdot}$deg이었다.