A dipole-moment function of MeH molecules (Me = Li, Na, K))

Abstract

The dipole-moment functions of the ground states of LiH, NaH, and KH molecules at small internuclear separations are calculated. Based on these calculations, the dipole-moment functions of molecules under consideration are derived for a wide range of internuclear separations. To this end, use was made of the cubic spline interpolation of the dipole-moment functions calculated in this work and those known ab initio.

Demonstrating the Potential of Alkali Metal-Doped Cyclic C6O6Li6 Organometallics as Electrides and High-Performance NLO Materials

“…The dipole moments of Li@C 6 O 6 Li 6, Na@C 6 O 6 Li 6 , and K@C 6 O 6 Li 6 organometallic complexes are 5.96 D, 6.34 D, and 7.84 D, respectively. The monotonic trend of the increase in the dipole moment reflects the more charge separation of charges with an internuclear distance, going from Li to K, which is indicative of their possible linear and nonlinear optical potential, similar to the work of Cherepanov and co-workers . For investigation of the linear optical response, the mean static polarizabilities (α o ) of newly designed electrides and the excess electron complex are investigated as well.…”

“…The monotonic trend of the increase in the dipole moment reflects the more charge separation of charges with an internuclear distance, going from Li to K, which is indicative of their possible linear and nonlinear optical potential, similar to the work of Cherepanov and co-workers. 74 For investigation of the linear optical response, the mean static polarizabilities (α o ) of newly designed electrides and the excess electron complex are investigated as well. α o of M@C 6 O 6 Li 6 complexes is in the range of 503 to 608 au, which is very high as compared to that of the pure C 6 O 6 Li 6 (136 au).…”

On some aspects of changing the sign of the dipole moment functions of diatomic molecules

“…in the asymptotic dipole moment function μ(R) = CR 3 is about nine times greater than the adjustable parameter C in the semiempirical calculations [16]. The polarity invariance for all R holds true for the ground states of the hydrogen halides HF, HCl and HBr [17], and alkali-metal hydrides LiH, NaH and KH [18] as well. Thus, the results of calculating the dipole moment functions at small separations for these molecules, though do not change the qualitative behaviour of the curves, however, lead to a quantitative improvement of the functions μ S (R).…”

“…The semiempirical methods are based on the asymptotic behaviour of the dipole moment function μ(R) = CR 3 at R → 0, with the coefficient C being an adjustable parameter whose sign and magnitude can take on incorrect values. A wrong choice of the sign of the coefficient C leads to a qualitative distortion of the dipole moment function in the range of small R. The problem of correct calculation of the functions μ(R) of manyelectron diatomic molecules at small internuclear separations was solved in [17][18][19], where an ab initio method for calculating the functions μ(R) was developed on the basis of the united-atom model and the formalism of irreducible tensor operators. The calculations performed within this approach allowed us to find general regularities in the behaviour of dipole moment functions of diatomic molecules at small internuclear separations [19].…”

Periodic law for the dipole moment functions of diatomic molecules at small internuclear distances

“…In spite of a long history of such investigations, nowadays reliable ab initio calculations of the dipole moment functions μ(R) of the molecules in the entire range of their internuclear separations R are lacking even for diatomic molecules. The existing semiempirical constructions of such dipole moment functions [1][2][3][4][5][6][7][8] are usually based on ab initio calculations (or experimental results) in some internuclear separation ranges including the vicinity of the equilibrium internuclear separation R e of the molecule, which is important for practical applications. Nowadays, existing computer codes based on ab initio methods are widely and efficiently used for calculating the dipole moment functions of diatomic molecules [9][10][11][12][13][14][15][16][17].…”