Dilead
- Formula: Pb2
- Molecular weight: 414.4
- CAS Registry Number: 12596-92-8
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Gas phase thermochemistry data
Go To: Top, Gas phase ion energetics data, Constants of diatomic molecules, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | 79.500 | kcal/mol | Review | Chase, 1998 | Data last reviewed in September, 1963 |
Quantity | Value | Units | Method | Reference | Comment |
S°gas,1 bar | 67.239 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in September, 1963 |
Gas Phase Heat Capacity (Shomate Equation)
Cp° = A + B*t + C*t2 + D*t3 +
E/t2
H° − H°298.15= A*t + B*t2/2 +
C*t3/3 + D*t4/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t2/2 + D*t3/3 −
E/(2*t2) + G
Cp = heat capacity (cal/mol*K)
H° = standard enthalpy (kcal/mol)
S° = standard entropy (cal/mol*K)
t = temperature (K) / 1000.
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Temperature (K) | 298. to 6000. |
---|---|
A | 8.934730 |
B | 0.394538 |
C | -0.001759 |
D | 0.000150 |
E | -0.020381 |
F | 76.75041 |
G | 77.82051 |
H | 79.50010 |
Reference | Chase, 1998 |
Comment | Data last reviewed in September, 1963 |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, Constants of diatomic molecules, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
B - John E. Bartmess
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
1.21 ± 0.10 | LPES | Sun, Sun, et al., 2009 | B |
1.366 ± 0.010 | LPES | Ho, Polak, et al., 1992 | B |
1.48 ± 0.10 | LPES | Sobhy, Reveles, et al., 2009 | Stated electron affinity is the Vertical Detachment Energy; B |
1.45 ± 0.10 | LPES | Ganteför, Gausa, et al., 1989 | B |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
6.1 ± 0.3 | EI | Saito, Yamauchi, et al., 1982 | LBLHLM |
Constants of diatomic molecules
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: Klaus P. Huber and Gerhard H. Herzberg
Data collected through May, 1977
Symbol | Meaning |
---|---|
State | electronic state and / or symmetry symbol |
Te | minimum electronic energy (cm-1) |
ωe | vibrational constant – first term (cm-1) |
ωexe | vibrational constant – second term (cm-1) |
ωeye | vibrational constant – third term (cm-1) |
Be | rotational constant in equilibrium position (cm-1) |
αe | rotational constant – first term (cm-1) |
γe | rotation-vibration interaction constant (cm-1) |
De | centrifugal distortion constant (cm-1) |
βe | rotational constant – first term, centrifugal force (cm-1) |
re | internuclear distance (Å) |
Trans. | observed transition(s) corresponding to electronic state |
ν00 | position of 0-0 band (units noted in table) |
State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Emission bands in the region 12500 - 11100 cm-1, observed in Ar and Ne matrices by excitation with argon/krypton ion laser lines. | ||||||||||||
↳Teichman and Nixon, 1976 | ||||||||||||
Absorption bands in the region 33400 - 34600 cm-1 (preceded by continuous fluctuations from 31300 to 33300 cm-1), 36800 - 38000, and 41000 - 42200 cm-1. | ||||||||||||
↳Weniger, 1967 | ||||||||||||
B | 19490.3 | 161.64 1 H | 1.036 | 0.0055 | B ↔ X 2 R | 19515.7 H | ||||||
↳missing citation; missing citation; Johnson, Cannell, et al., 1972 | ||||||||||||
A | 14465.6 | 162.4 1 | 0.4 | A ↔ X 3 (R) | 14491.5 | |||||||
↳missing citation; Johnson, Cannell, et al., 1972; Puri and Mohan, 1975 | ||||||||||||
State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
X | 0 | 110.5 1 4 H | 0.35 |
Notes
1 | Constants obtained by Johnson, Cannell, et al., 1972 from a reclassification of bands in the blue-green and in the red system. The new analysis of the ground state seems to be confirmed by the observation of a lower state frequency of 111 cm-1 in laser-excited matrix emission spectra [see Teichman and Nixon, 1976 who attribute the 111 cm-1 interval to a matrix-induced splitting of the ground state]. The revised lower state constants imply, however, a strong contradiction to the usual rule that if ω' > ω" then B' > B" since according to the published spectrograms of Weniger, 1967 the B-X bands are strongly shaded to the red, i.e. B' < B". |
2 | Previously called A-X. Also observed in inert gas matrices Brewer and Chang, 1972, Teichman and Nixon, 1976. |
3 | Previously believed to have B as its lower state. |
4 | Johnson, Cannell, et al., 1972 give 119.1 which seems to be a typographical or arithmetical error since it does not represent the band head measurements of Shawhan, 1935. |
5 | Thermochemical value (mass-spectrom.) Gingerich, Cocke, et al., 1976. |
References
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Constants of diatomic molecules, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Chase, 1998
Chase, M.W., Jr.,
NIST-JANAF Themochemical Tables, Fourth Edition,
J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]
Sun, Sun, et al., 2009
Sun, Z.; Sun, S.T.; Liu, H.T.; Zhu, Q.H.; Gao, Z.; Tang, Z.C.,
Photoelectron Spectroscopic and Theoretical Studies of MmC6F5 Anionic Complexes (M = Ph and Bi; m=1-4),
J. Phys. Chem. A, 2009, 113, 28, 8045-8054, https://doi.org/10.1021/jp8099626
. [all data]
Ho, Polak, et al., 1992
Ho, J.; Polak, M.L.; Lineberger, W.C.,
Photoelectron Spectroscopy of Group-IV Heavy Metal Dimers - Sn2-, Pb2-, and SnPb-,
J. Chem. Phys., 1992, 96, 1, 144, https://doi.org/10.1063/1.462503
. [all data]
Sobhy, Reveles, et al., 2009
Sobhy, M.A.; Reveles, J.U.; Gupta, U.; Khanna, S.N.; Castleman, A.W.,
Photoelectron imaging and theoretical investigation of bimetallic Bi1-2Ga0-2- and Pb-1-4(-) cluster anions,
J. Chem. Phys., 2009, 130, 5, 054304, https://doi.org/10.1063/1.3069295
. [all data]
Ganteför, Gausa, et al., 1989
Ganteför, G.; Gausa, M.; Meiwes-Broer, K.H.; Lutz, H.O.,
Photoemission from Tin and Lead Clusters Anions,
Z. Phys. D, 1989, 14, 1-4, 405, https://doi.org/10.1007/BF01426983
. [all data]
Saito, Yamauchi, et al., 1982
Saito, Y.; Yamauchi, K.; Mihama, K.; Noda, T.,
Formation and ionization potentials of lead clusters,
Jpn. J. Appl. Phys., 1982, 21, 396. [all data]
Teichman and Nixon, 1976
Teichman, R.A., III; Nixon, E.R.,
Absorption and laser-excited emission spectra of matrix-isolated Pb2,
J. Mol. Spectrosc., 1976, 59, 299. [all data]
Weniger, 1967
Weniger, S.,
Etude du spectre d'absorption de la molecule de plomb,
J. Phys. (Paris), 1967, 28, 595. [all data]
Johnson, Cannell, et al., 1972
Johnson, S.E.; Cannell, D.; Lunacek, J.; Broida, H.P.,
New molecular constants for the ground electronic state of Pb2,
J. Chem. Phys., 1972, 56, 5723. [all data]
Puri and Mohan, 1975
Puri, S.N.; Mohan, H.,
Thermal emission spectrum (intercombinational system) of Pb2,
Indian J. Pure Appl. Phys., 1975, 13, 206-207. [all data]
Brewer and Chang, 1972
Brewer, L.; Chang, C.-A.,
Matrix isolation of Pb and Pb2,
J. Chem. Phys., 1972, 56, 1728. [all data]
Shawhan, 1935
Shawhan, E.N.,
Band spectrum of Pb2 in absorption and emission,
Phys. Rev., 1935, 48, 343. [all data]
Gingerich, Cocke, et al., 1976
Gingerich, K.A.; Cocke, D.L.; Miller, F.,
Thermodynamic investigation of the lead molecules Pb2, Pb3, and Pb4 by mass spectrometry,
J. Chem. Phys., 1976, 64, 4027. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Constants of diatomic molecules, References
- Symbols used in this document:
EA Electron affinity S°gas,1 bar Entropy of gas at standard conditions (1 bar) ΔfH°gas Enthalpy of formation of gas at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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