Title

Measuring the Microwave Spectrum of 3,4-Difluorophenol

School Name

South Carolina Governor's School for Science and Mathematics

Grade Level

12th Grade

Presentation Topic

Chemistry

Presentation Type

Mentored

Abstract

This study measured the microwave spectrum of the chemical 3,4-difluorophenol in order to determine the structure of the molecule. The microwave spectrum of 3,4-difluorophenol was measured in the range of 8-18 GHz using a chirped microwave pulse. 10,000 averages were taken for each frequency range. Density functional theory calculations were performed using Gaussian 03W in order to obtain the predicted rotational spectra of the compound. Gaussian yielded three rotational constants, A, B, and C for 3,4-difluorophenol, whose values are 3071.31 MHz, 1301.36 MHz, and 914.84 MHz, respectively. These values measure the chemical’s resistance to rotational motion. The distortion constants, which measure the flexibility of the chemical, were also computed. For the analysis of the spectrum the software programs SPCAT and SPFIT were used to determine rotational constants from the experimental data. This study was able to successfully analyze the experimental values of A, B and C whose values are 3079.42, 1307.43, and 917.84 MHz, respectively, as well as the distortion constants of the chemical. The overall RMS error of the predicted values and measured values is 0.000654 MHz.

Location

HSS 202

Start Date

4-2-2022 9:45 AM

Presentation Format

Oral Only

Group Project

Yes

COinS
 
Apr 2nd, 9:45 AM

Measuring the Microwave Spectrum of 3,4-Difluorophenol

HSS 202

This study measured the microwave spectrum of the chemical 3,4-difluorophenol in order to determine the structure of the molecule. The microwave spectrum of 3,4-difluorophenol was measured in the range of 8-18 GHz using a chirped microwave pulse. 10,000 averages were taken for each frequency range. Density functional theory calculations were performed using Gaussian 03W in order to obtain the predicted rotational spectra of the compound. Gaussian yielded three rotational constants, A, B, and C for 3,4-difluorophenol, whose values are 3071.31 MHz, 1301.36 MHz, and 914.84 MHz, respectively. These values measure the chemical’s resistance to rotational motion. The distortion constants, which measure the flexibility of the chemical, were also computed. For the analysis of the spectrum the software programs SPCAT and SPFIT were used to determine rotational constants from the experimental data. This study was able to successfully analyze the experimental values of A, B and C whose values are 3079.42, 1307.43, and 917.84 MHz, respectively, as well as the distortion constants of the chemical. The overall RMS error of the predicted values and measured values is 0.000654 MHz.