Accurate High‐Pressure Measurements of Carbon Monoxide's Electrical Properties. Issue 6 (15th February 2018)

• Record Type: Journal Article
• Authors: Tsankova, Gergana; Richter, Markus; Stanwix, Paul L.; May, Eric F.; Span, Roland
• Is Part Of: Chemphyschem. Volume 19:Issue 6(2018)
• Page Start: 784
• Page End: 792
• Publication Date: 2018-02-15
• Subjects: carbon monoxide -- dielectric permittivity -- microwave re-entrant cavity resonator -- molar polarizability -- second dielectric virial coefficient; Chemistry, Physical and theoretical -- Periodicals; 541.05
• DOI: 10.1002/cphc.201701085
• Languages: English
• ISSNs: 1439-4235

Abstract

Abstract: Accurate measurements of carbon monoxide's electrical properties were carried out at high pressure for the first time enabling stringent comparisons with theoretical values calculated ab initio. Dielectric permittivity measurements were conducted utilising a microwave re‐entrant cavity resonator over the temperature range from (255 to 313) K and at pressures up to 8 MPa with a relative combined expanded uncertainty ( k =2) less than or equal to 52 ppm. The new data enable carbon monoxide's molar polarizability to be correlated within 0.5 %, significantly improving upon existing literature data, which have a relative scatter of about 10 %. The measured molecular polarizability and electric dipole moment of carbon monoxide were determined to be 2.176×10 −40 C 2 m 2 J −1 and 0.107 D. Literature values from ab initio calculations for these properties are within 0.28 % and 3.9 %, respectively, of the measured quantities. Moreover, our measurement of the electric dipole moment at finite temperature agrees within 2.2 % with the value derived from accurate spectroscopic measurements for the ground rovibrational state. The second dielectric virial coefficient of carbon monoxide was determined experimentally for the first time to be b ϵ =(1.015±0.044) cm 3 mol −1, which compares reasonably with ab initio estimates. Abstract : Under pressure : Accurate measurements of carbon monoxide's electrical properties were carried out at high pressure for the first time enabling stringent comparisons with theoretical values calculated ab initio. The measurements were carried out in the temperature range from 255 K to 313 K and at pressures up to 8 MPa utilising a microwave re‐entrant cavity resonator. Data for dielectric permittivity, molar and molecular polarizability as well as for electric dipole moment and second dielectric virial coefficient were obtained.