Actinide Metal Atom (Th and U) Reactions to Form Novel Molecules
Metal-Carbon Multiple BondsActinide Metal Hydrides
Lester Andrews, Chemistry Department, University of Virginia, Charlottesville, Virginia
Also Jon Lyon, Han-Gook Cho, Xuefeng Wang,Bjorn Roos, Han-shi Hu, Jun Li, Colin Marsden,
Laura Gagliardi
Apparatus for Laser Ablation and Matrix Isolation
7 Ko r 4 K
1 0 6 4 n m
M e ta lTa rg e t
A r / C H C H X N e /C H o r C H X
4 3
4 3
o ru v, v is
CsI window for IR
YAG laser ablation of Zr
9.17.00 1:37 PM8 3.3 Periodic Table
Reading the Periodic Table: ClassificationReading the Periodic Table: ClassificationNonmetals, Metals, Metalloids, Noble gases
Novel Organometallic Molecules
M + CH4 CH3—MH ↔ CH2=MH2 ↔ HC≡MH3
M + CH3X CH3—MX ↔ CH2=MHX ↔ HC≡MH2X
M + CH2X2 CH2X—MX CH2=MX2 HC≡MHX2
M + CHX3 CHX2—MX CHX=MX2 HC≡MX3
M + CX4 CX3—MX CX2=MX2 XC≡MX3
B3LYP density functional calculated structures for methylidene molecules
C C C C C
CC
Y Zr Nb Mo Ru
ThU
C Tc
Infrared spectra of the Th + CH4 reaction productJ. Phys. Chem. A 2005, 105, 6796.
Dep at 7 K
240-380 nm
> 220 nm
Anneal 26 K
> 420 nm
Observed and Calculated (B3LYP/6-311++G(3df,3pd)/SDD) Frequencies for CH2=ThH2
ApproximateModeDescription
CH2=ThH213CH2=ThH2 CD2=ThD2
Obs. Calc. Int. Obs. Calc. Int. Obs. Calc. Int.
CH2 stretch 3142.6 2 3132.2 2 2321.7 2
CH2 stretch 2861.4 11 2854.9 11 2084.7 2
ThH2 stretch 1435.7 1434.9 350 1435.7 1434.8 350 b 1023.5 110
ThH2 stretch 1397.1 1394.2 698 1391.7 1394.2 698 b 1005.7 98
CH2 bend 1327.5 11 1320.5 11 989.0 340
C=Th stretch 670.8 679.6 178 651.5 659.7 173 602.9 614.8 127
CH2 wag 634.6 633.0 161 629.2 627.5 157 499.2 495.1 109
ThH2 bend 458.7 492.8 110 492.3 108 355.8 34
ThH2 rock 460.8 5 458.2 4 344.4 29
CH2 twist 343.0 30 342.5 30 245.3 18
ThH2 wag 321.9 65 321.6 66 230.2 30
CH2 rock 248.4 62 248.1 62 177.5 30
CH2=ThH2, CH2=ThHF, CH2=UH2, CH2=UHF
1 4 8 0 1 3 8 01 4 3 0
W a v e n u m b e rs (c m )-1
0 .0 0
0 .1 6
0 .3 2
Abs
orba
nce
T h + C H 4
U + C H 4
U + C H F3
T h + C H F3
(a )
(b )
(c )
(d )
C H F3
C H F3
CH2=UHF
CH2=ThHF
Structures calculated with different theoretical methodsInorg. Chem. 2007, 46, 4917.
BPW91/PW91/CASPT2
One singly-occupied U 5f orbital in CH2=UH2
Reactions of laser-ablated U atoms with CH2XY (XY = F2, FCl, and Cl2) lead to a series of new actinide methylidene complexes CH2=UF2,
CH2=UFCl, and CH2=UCl2, which have agostic structures stabilized by interaction through the open-shell U 6d-5f orbitals.
Angew. Chem. Intl. Ed. 2007, 46, 9045.
Structures for Th, U and NH3 Reaction ProductsChem. Eur. J. 2007, 13, 5601.
B3LYP/CCSD
1 .90 31 .01 5
17 3 .3 o2 .04 9
2 .04 110 1 .6 o
10 0 .7 o
2 .19 3
2 .07 3
1 .01 8
1 .01 7
10 7 .6 o
12 9 .8 o
1 2 2 .6 o
10 4 .0 o
2 .1 7 6(2 .1 9 6 )
2 .0 3 7(2 .0 5 4 )1 2 7 .1
(1 2 6 .8 )
11 7 .9(11 8 .0 )
1 3 3 .7(1 3 4 .0 )
1 .0 2 3(1 .0 2 2 )
1 .0 1 4(1 .0 1 3 )
2 .1 0 3 (2 .1 0 9 )
1 .9 5 1 (1 .9 6 6 ) 1 .0 1 4
(1 .0 1 3 )
1 7 2 .9 (1 7 3 .0 )
1 0 2 .4 (1 0 2 .0 )
1 0 0 .6 (1 0 3 .2 )
H-N=ThH2 H-N=UH2
1.9031.951
62.1% d
30.1% fHOMO
46.2% d
48.5% fHOMO
CH2=ThH2
2.103
CH2=UH2
2.045
Small amount of triple bond character
Novel Organometallic Molecules
M + CH4 CH3—MH ↔ CH2=MH2 ↔ HC≡MH3
M + CH3X CH3—MX ↔ CH2=MHX ↔ HC≡MH2X
M + CH2X2 CH2X—MX CH2=MX2 HC≡MHX2
M + CHX3 CHX2—MX CHX=MX2 HC≡MX3
M + CX4 CX3—MX CX2=MX2 XC≡MX3
Th atom reactions with CHF3, CHF2Cl, CHFCl2, and CHCl3
5 8 0 4 8 0W a v e n u m b e rs (c m )
-1
0 .0 0
0 .4 5
Abs
orba
nce
( a )
(b )
(c )
(d )
CHF3
Approximate HC÷ThF3 DC÷ThF3
Mode Obs.(argon matrix) B3LYP Calc. (int.) Obs.(argon matrix) B3LYP Calc. (int.)
C-H stretch, a1 3108.6 (5) 2288.6 (0)
Th-F stretch, a1 565.4 568.5 (17) 563.4 566.0 (30)
Th-F stretch, e 521.3 526.0 (419) 520.6 525.7 (404)
C-Th stretch, a1 502.1 508.9 (180) 493.1 492.3 (160)
H-C-Th bend, e 425.9 (68) 328.3 (56)
F-Th-F bend, a1 120.5 (1) 117.4 (4)
F-Th-F bend, e 117.5 (27) 115.4 (27)
C-Th-F bend, e 106.0 (37) 102.0 (17)
Observed and Calculated Fundamental Frequencies for HC÷ThF3 in C3v
Symmetry in the Triplet Ground Electronic StateEur. J. Inorg. Chem. 2008, in press.
Energies of Th and U atom reactions with CHF3 and CF4
• 2.48 Å 2.16 Å 2.41 Å 2.13 Å 1.94 Å
CHF2--ThF CHF=ThF2 HC—ThF3 CHF=UF2 HC≡UF3
+76 kcal/mol + 46 kcal/mol 0 kcal/mol + 23 kcal/mol 0 kcal/mol
2.26 Å 2.47 Å 2.40 Å
CF2=ThF2 CF2—ThF2 FC—ThF3
+ 51 kcal/mol + 51 kcal/mol 0 kcal/mol
2.45 Å 2.40 Å 2.01 Å
CF2—UF2 CF2=UF2 FC≡UF3
+ 21 kcal/mol + 20 kcal/mol 0 kcal/mol
C
Th
H 1.0932 .36 8
2.085
109.
4
109.5
C
Th
Cl
Cl Cl
1.0922 .36 2
2.594
107.
1
111.7
C
Th
F
F F
1.0922 .41 2
2.123
108.
2
110.7
C
Th
F
F F
F 1.3002 .39 7
2.120
109.
5
109.4
C
Th
Cl
Cl Cl
Cl1.6592 .35 4
2.592
107.
9
110.9
C
Th
Cl
Cl
1.2942 .36 9
2.604
109.
0
110.1
C
ThCl
Cl1.6672 .38 6
2.621
110.4
H
H H
H H
F
FF
F
2.096
109.1
109.8
109.
1 109.0
108.8
2.108
C
Th
Cl
Cl1.092
2 .37 9
2.608
108.
0
112.1
C
ThCl
1.0922 .39 5
2.623
111.3FF
F
2.100
107.2
111.1
107.
6 108.1
110.9
2.109
HH
B3LYP Structures for HC-ThX3 and XC-ThX3 Complexes
N a tu ra l C h arg es
0 .1 0
-0 .8 4
3 .11-0 .7 9 (x 3 )
S p in D en s itie s
-0 .0 7
1 .8 7
0 .1 7 0 .0 1 (x 3 )
Uranium atom reaction productsProc. Natl. Acad. Sci. 2007, 104, 18919.
0 .9 0
0 .0 0
Abs
orba
nce
5 8 0W a v e n u m b e rs (c m )
-1 5 0 0(a )(b )(c )
(d )(e )( f)
(g )(h )( i)
P
P
U F 5 U F 3
U+CDF3
U+CF4
U + CDF3
U + CF4
U + CDF3
U + CHF3
Observed and calculated (PW91/TZ2P) fundamental vibrational
frequencies for the C3v F3U≡CX (X = H, D, F) molecules
• Mode description F3U≡CH
F3U≡13CH F3U≡CD F3U≡CF
Obs. Calc. Obs. Calc. Obs. Calc. Obs. Calc.
C-X str, a1 2979(0.1) 2969(0.2) – 2200(1.5) – 1268(312)
U≡CX str, a1 – 747(46) -- 721(42) – 717(41) – 441(34)
U-F sym str, a1 576.2 585(122) -- 585(123) 576.2 586(123) 578.7 589(118)
U-F antisym str, e 540.2 561(284) 539.2 559(280) 535.9 541(207) 536.4 544(177)
U≡C-X bend, e 527.5 508(34) -- 506(24) -- 412(49) – 311(28)
Calculated structures of (a) F3U≡CH, (b) Cl3U≡CH, (d) Br3U≡CH, and (d) F3U≡CF
Comparison of the molecular orbitals of ethyne HC≡CH and the uranium-methylidyne F3U≡CH and F3U≡CF complexes (isosurface =0.05 atomic unit)
HC≡CH F3U≡CH F3U≡CF
π1-MO
π2-MO
σ-MO
Uranium atom reaction productsA
bsor
banc
e
1 .0
0 .05 4 0 4 2 0
W a v e n u m b e rs (c m )-1
(a )(b )(c )(d )
(e )( f)
(g )(h )
( i)( j)(k )( l)
C H B r 3
CHCl3
13CHCl3
CDCl3
CHBr3
Observed and calculated (PW91/TZ2P) fundamental vibrational
frequencies for the C3v X3U≡CH (X = Cl, Br) molecules
•Mode description Cl3U≡CH Cl3U≡13CH Cl3U≡CD Br3U≡CH
Obs.b Calc. Obs. Calc. Obs. Calc. Obs. Calc.
C-H str, a1 3001(2) 2991(2) 2219(7) 3005(3)
U≡CX str, a1 –c 770(69) –c 744(65) –c 738(64) –c 777(70)
U≡C-H bend, e 527.2 522(224) 522.8 518(218) 415.9 410(216) 527.6 527(178)
U-X sym str, a1 339(29) 339(29) 339(29) 225(84)d
U-X antisym str, e 329(140) – 329(140) – 326(100) 216(10)d
Carbon-Uranium Triple Bonds
•
• 1.764 Å 1.808 Å 1.910 Å
• C≡U≡O HC≡UCl3
• PW91 bond lengths • Zhou, Andrews, Li, Bursten, Lyon, Hu, Andrews, Li,• J. Am. Chem. Soc. 1999, 121, 9712. Proc. Natl. Acad. Sci. U.S.• Earlier work: 2007, 104(48), 18919.• Tague, Andrews, Hunt,• J. Phys. Chem. 1993, 97, 10920. • Pyykko, Li, Runeberg,
• J. Phys. Chem. 1994, 98, 4809.
Reactions of Mo atoms with CHX3 molecules:
HC≡MoX3
Reactions of Mo atoms with CHX3 moleculesOrganometallics, 2007, 26, 6373.
9 7 0
(a )
(b )
(c )
(d )
9 9 5W a v e n u m b e rs (c m )
-1
0 .0 0
0 .0 4
Abs
orba
nce
9 2 9 8
1 0 0
CHF3
CHF2Cl
CHFCl2
CHCl3
Natural Mo isotopic splittings
ApproximateDescription
HC≡MoCl3 DC≡MoCl3 HC≡MoF3
obs calc int obs calc int obs calc int
C-H str, a1 3058.2 3212.2 35 2296.2 2387.9 24 3073.1 3221.2 39
HC≡Mo str, a1 978.1b 1051.9 8 932.4b 1005.8 6 986.0c 1065.0 20
Mo-X str, e 438.7 425.0 81x2 436.4 423.0 74x2 689.2 683.4 210x2
Mo-X str, a1 380.8 9 380.7 9 664.6 651.7 60
H-C-Mo def, e 658.9 660.2 76x2 533.4 533.6 52x2 645.4 642.7 30x2
C-Mo-X def, e 237.7 7x2 212.3 7x2 288.7 5x2
Mo-X3 umb, a1 144.0 0 143.7 0 228.0 9
Mo-X2 bend, e 100.4 0 100.4 0 163.6 8x2
Observed and Calculated [B3LYP/6-311++G(2d,p) ] Fundamental Frequencies of HC≡MoX3 Complexes in the Ground 1A1 Electronic State with the C3v Structure
Span the periodic table
U + H2
U in solid para-hydrogen at 4 KJ. Phys. Chem. A, 2007, 111, 6383.
1 5 0 0 1 4 0 0 1 3 0 0 1 2 0 0 11 0 0 1 0 0 0
0 .0 0
0 .0 5
0 .1 0
Abs
orba
nce
W av en u m b ers (c m )-1
(a )
(b )
(c )
(d )
d ep o sitio n
irrad ia tio n (> 5 3 0 n m )
irrad ia tio n (> 4 7 0 n m )
an n e a lin g to 7 K
U + -Hp 2
U H (H )4 2 x
U H (H )2 2 x
(H ) U H2 x 2 2
p -H 2
U H 4 U H 2
Th in solid H2, HD, and D2 at 4 KJ. Phys. Chem. A, 2008, in press.
1500 1400 1300 1200 1100 1000 9000.00
0.20
0.40
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
Wavenumbers (cm )-1
Abs
orba
nce
ThH (H )4 2 x
ThD (D )4 2 x
ThD4
ThD2
ThH4
ThH2
(i)
(j)
(k)
CH4
Ground state total CASSCF electron density
WH4 (triplet) ThH4(singlet) UH4(triplet)
WH44H2 (singlet) ThH44H2(singlet) UH46H2(triplet)
Ball Game!!!
• We have investigated reactions of the laser-ablated actinide metal atoms Th and U with small molecules, and assigned the new reaction products from matrix infrared spectra and comparison with DFT calculated isotopic frequencies. These new molecules are important for their unique bonding and structure and their unusual chemistry.
• We thank NSF for support and you for your kind attention.
Matrix-Isolation
Spectroscopy
Synthesis
Gas-Phase Theory
PERSPECTIVE