Magnetic properties and molecular quadrupole moment of HF and HCl by molecular-beam electric-resonance spectroscopy

Abstract

The radio-frequency spectra of HF and H 35Cl in an external electric and magnetic field are measured using a high-resolution molecular-beam electric-resonance spectrometer. The measurements are in the lowest vibrational state ( v = 0) and the first rotational state ( J = 1). The spectra are analyzed using a standard Hamiltonian. The magnetic properties of the molecules are derived using methods introduced by Ramsey. The results, corrected for the effects of molecular vibrations, are: HF H 35Cl g J 0.74104(15) 0.45935(9) χ | - χ δ ( kHz/(kG) 2 ) 0.132(6) −0.048(18) (χ | - χ δ) d (10 −6 erg/G 2·mole ) 1.342(25) 3.49(10) (σ | - σ δ) H ( ppm) 24(9) 21(5) (σ | - σ δ) H d ( ppm) −96(9) −148(7) (σ | - σ δ) hal ( ppm) 108(9) 300(24) (σ | - σ δ) hal d ( ppm) −1(9) −4(25) θ (10 −26 esu cm 2 ) 2.36(3) 3.74(12) Numbers in parentheses are the errors in the final significant figures. Generally good agreement is found with existing ab initio calculations.