Title : On a new approach to determining the ionization potential of molecules from spectroscopic data
Abstract:
A new on principle approach has been developed for determining the adiabatic ionization potential Io(MX) of polar eM2+X– molecules with high accuracy (no worse than 0.02 eV) using spectroscopic data only. This approach is based on measurement of difference of Stark displacements DEo=½α¢(e¢)2–½α"(e")2 by internal field of X– anion with strength e=e/ in eM2+X– molecule of its electronic terms formed by non-bonding e electron orbitals located at M2+ on distance ro from X–. The molecular transition between the lowest non-bonding e electron orbitals observes in spectrum as the Rydberg series beginning To(MX) displaced from an atomic line E(M) on DEo=To(MX)–E(M) named by the optical shift which is immediately connected with the desired Io(MX) as follows from: Io(MX) = Io(M) – Thus all magnitudes in formula for Io(MX) are found only from the MX, M and M+ spectra. The adiabatic ionization potentials of MX molecules with evaluated upper limit of its error ±0.019 eV are presented below.
|
Metal |
Parameter |
F |
Cl |
Br |
J |
|
Ca E(Ca)=15227.969 cm–1 E(Ca+)=25302.955 cm–1 Io(Ca)=6.113213 eV Io(Ca+)=11.8718 eV |
, Å |
1.955110(42) |
2.43991097(15) |
2.59635350(96) |
2.83130(30) |
|
, Å |
1.958543(44) |
2.420655(16) |
2.568866(28) |
2.78275(47) |
|
|
To(B2S+), cm–1 |
18833.136(52) |
16855.144(10) |
16383.113(15) |
15716.7502(78) |
|
|
Io(CaX), eV |
5.533 |
5.873 |
5.947 |
6.047 |
|
|
Sr E(Sr)=14573.478 cm–1 E(Sr+)=24115.92 cm–1 Io(Sr)=5.694901 eV Io(Sr+)=11.0302 eV |
, Å |
2.0785831(17) |
2.5787221(18) |
2.7375185(54) |
2.97578928(43) |
|
, Å |
2.0833525(96) |
2.559340(11) |
2.709809(14) |
2.929918(11) |
|
|
To(B2S+), cm–1 |
17264.1418(24) |
15725.1112(18) |
15355.7795(34) |
14820.1619(7) |
|
|
Io(SrX), eV |
5.257 |
5.523 |
5.581 |
5.661 |
|
|
Ba E(Ba)=9315.351 cm–1 E(Ba+)=5274.337 cm–1 Io(Ba)=5.2117053 eV Io(Ba+)=10.004 eV |
, Å |
2.16217706(38) |
2.68540585(24) |
2.84657693(35) |
3.0867767(41) |
|
, Å |
2.20723(10) |
2.7367397(45) |
(2.893±0.023) |
3.1275903(48) |
|
|
To(B2S+), cm–1 |
14040.15(2) |
11867.3380(20) |
11325 |
10421.91246(54) |
|
|
Io(BaX), eV |
4.587 |
4.879 |
4.956±0.02 |
5.074 |
|
|
Yb E(Yb)=18330.278 cm–1 E(Yb+)=28727.025 cm–1 Io(Yb)=6.25394 eV Io(Yb+)=12.184 eV |
, Å |
2.019182(98) |
2.490915(13) |
— |
— |
|
, Å |
1.98967(40) |
(2.442±0.005) |
— |
— |
|
|
To(B2S+), cm–1 |
21073.33(50) |
19938.4(33) |
— |
— |
|
|
Io(YbX), eV |
5.872 |
6.040 |
— |
— |
It is proposed to make this approach by part of the spectroscopic studies along with the determination of other molecular parameters from the spectra: vibrational, rotational and electronic ones.
