The conformations of some simple alcohols and thiols

Internal Rotation of Methylcyclopropane and Related Molecules: Comparison of Experiment and Theory

“…Theoretical and refined internal rotation potential energy functions for cyclopropanol (CP–OH). The experimentally observed infrared transitions , are also shown. The frequencies in parentheses correspond to calculated values.…”

“…They reported the energy minimum to be 106° ± 5° and estimated the cis barrier to be 7.9 kJ/mol (660 cm –1 ) and the trans barrier to be ∼17 kJ/mol (1420 cm –1 ). In a later work they reported early ab initio calculations using a 4–21G basis set. These show a potential energy function, where the barrier between the two gauche configurations ( cis barrier) is ∼900 cm –1 (10.8 kJ/mol) and the barrier between the trans and gauche configurations ( trans barrier) is ∼700 cm –1 (8.4 kJ/mol).…”

“…In the present study we performed high-level ab initio calculations for each of these molecules and also for cyclopropanol (CP–OH) and cyclopropanethiol (CP–SH) to assess how well the theoretical calculations do for predicting the barriers and potential energy functions. Experimental microwave results have been previously reported for CP–OH and CP–SH, and low-level theoretical calculations were also performed on CP–OH . The far-infrared spectrum of cyclopropylamine (CP–NH 2 ) has previously been studied by Kalasinsky and co-workers, and a potential energy function was determined.…”

Libro de resúmenes del ECI 2020 de verano

“…In our laboratory we have experimentally determined the barriers to rotation of methylcyclopropane (CP-CH3) [8], propylene oxide (CPO-CH3) [8], and propylene sulfide (CPS-CH3) [8] using Raman spectroscopy; cyclopropylsilane (CP-SiH3) [9,10] and cyclopropylgermane (CP-GeH3) [10] were investigated using mid-infrared combination band spectra. Experimental microwave results have been previously reported for CP-OH [11] and CP-SH [12], and low level theoretical calculations were also performed on CP-OH [13]. The far-infrared spectra of cyclopropylamine (CP-NH2) has previously been studied by Kalasinsky and co-workers [14] and a potential energy function was determined.…”

“…En nuestro laboratorio hemos determinado experimentalmente las barreras de rotación de metilciclopropano (CP-CH3) [8], óxido de propileno (CPO-CH3) [8], y sulfuro de propileno (CPS-CH3) [8] usando espectroscopía Raman; ciclopropilsilano (CP-SiH3) [9,10] y ciclopropilgermano (CP-GeH3) [10] fueron investigados usando combinaciones de bandas espectrales en el infrarrojo medio. Resultados experimentales de microonda fueron previamente reportados para CP-OH [11] y CP-SH [12], y cálculos teóricos de bajo nivel fueron también efectuados para CP-OH [13]. El espectro infrarrojo lejano de cyclopropilamina (CP-NH2) ha sido previamente estudiado por Kalasinsky y colegas [14] y una función de energía potencial fue determinada.…”