Mid-, far-infrared and raman spectra of uranyl complexes in aqueous solutions

459

Joumnl of Molecular Structure, 114 (1984) 459-462 Elsevier Science Publishers B.V., Amsterdam - Printed in The Netherlands

MID-,

FAR-INFRARED

AND

RAMAN

P.L.GOGGIN*

and

J.MINK3*

M-GAL,

SPECTRA

OF

URANYL

COMPLEXES

IN AQUEOUS

SOLUTIONS

'Etitvijs Lo&d University Department of General and Inorganic Chemistry, H-1445 Budapest (Hungary; 2 Department of Inorganic Chemistry, The University, Bristol 858 1TS (Gt.Britain) 3 Institute of Isotopes of the Hungarian Academy of Sciences, H-1525 Budapest (Hungary)

ABSTRACT Vibrational Na3LU02F5

spectra

over

a range

after'water There

was

four

subtraction

for

aqueous

ligand,

can

constants

[UO2F]+

but

both

for

and

that

solution

some

and

water

[UO2Cl]*

monodentate

and

of UO2C104,

distances

were

but

complexes

The

bound

to [UO$ [U021

been

From

sulphate.

for

nor

of acetate

species

present

uranyl

solvated

'+_ 2+

established.

to bidentate

linkage

main

calculated

are

of H20

besidessolvated

have

neither

and

absorptions

molecules

bidentate

complexes.

to a monodentate

UO bond

residual

coordination,

featuresdo:notrefer

acetate

be ascribed

The

composition.

suggest

stretching

established

lution

obtained

of perchlorate

of weak

nitrate

dentate were

of solution

no evidence

ion formation The

been

, U02F2,[ Bu4N121U02C141 , UO2C12, U02(N0312, I Pr4NltU02(02CCH3)31 > [ Pr4Nl WO2(N03)31 , UO$O$CH&.

RbIU02(N03)31 UO2S0,

have

I, L NH4131U02F51

to mono-

to uranyl

in U02SD4

frequencies

so-

force

complexes.

INTRODUCTION The and

technical

especially

troscopy aqueous

can

difficulties in the

be used

solutions

attention.

in solid

to detect

of

of uranium,

vibrational

the its

spectroscopic

state

and

in studying

i-t-. are

of uranyl

Because

extraction

far

complex

of aqueous known

formations

in water

complexes

in the

infrared

of the

UOEf

salts

and

is a valuable

complexes

has guide

here.

been for

have

been for

interpreting

solutions

ment found ic ligand.

in solids after dissolution in water In this paper we report infrared and

The

persistance

Elsevier Science

Publishers

in the

of

cases

solutions. attracted

through videly many

mid

i-r-.

Rarran specStudies very

on

little

its role

in the

studied.

Detailed

of the

the nature

of

the coordination

uranyl the

salts species

environ-

depends on the nature of inorganRaman studies of uranyl salts.

*Present address: Institute of Inorganic Chemistry, Niirnberg, Egerlandstr. 1, D-8520 Erlangen (F.R.G.)

0 1954

have

group

reported

in aqueous

0022-2860/84/$03.00

solutions

.In favorable

[l]

importance analysis

studied

well

B.V.

University

of Erlangen-

EXPERIMENTAL Infrared 7199a

spectra

Fourier

mini-cell

with

of aqueous

solutions

te effects. used

Krypton

be.given

AND most

results

fluoride

to reconcile the

1

than

Raman

spectra

1. From

bands spectra

in . agreement can

any

1106

UO2

sumrized

spectra

: INFRARED

(198 400

hitherto;

stretching

will AND

implv

with

the

Instruments

far

12 pm was

solvent

and

different

photon

was

used,

electroly-

systems.

counter

Model

One

detection.

52 Argon

ion or

a Jobin-Yvon-Ramanor

spectrometer,

using

Preparation

lasers.

of uranyl

the

HG-25

excitation

of compounds

Raman

somewhat Four

salts.

bands.

All

in Table

2. More

be

elsewhere

RAMAN

BANDS

all

from

will

The

, 253

s

160 b,w

two

available

complex

m (82.7 w,p) sh.

coordinated

U02

modes

U02

evi-

may

ac-

complete

SOLUTIONS OF

[C104]-

bending stretch or coordinated libration

modes

UF stretch

of [U02F]+ of.[U02F]+

diffi-

of aqueous

of the

ASSIGNMENT

in

not

SPECIES

not

U(OH,)S

._

modes

IN AQUEOUS

C

908

are

were

of acetate

discussion

131.

listed

frequencies

uranyl

of

formation

sulphate

types

COMPLEXES

U-OH2

380

et al.

systems

[2].

HYDRATED

vs,pja

and

solution

no evidence

of Brooker

stretching

acetate

detailed

OF URANYL

w

found

other

stronger

NO3

Free

in aqueous

was

studies

for

uranyl

given

complexes

of perchlorate

model.

w,b

Fluorides

for

two

APPROXIMATE

vs,'(874 w,dp),

spectra

Laboratories

with

(cm“) b

vs, 627

962.5

i.r.

with

be detected

simple

of dissolved

are

Perchlorates

an AgCl

For

instrument

Krypton-ion

indicated with

two

a

used

films.

Nicolet

of approximately

performed

EXPERIMENTAL DATA

experiments

monochromator

on fluorides

the

vibrational

TABLE

with

i-r.

to compensate

monochromator

interaction

cult

solutions

cell

Radiation

vibrational

to [U02]2'

with

for

recorded mid

[2].

in Table

1. Our

dent;in

were

other

and

the

24 urn liquid

employed

triple

double

Argon-

uranyl-anion

count

The

prominent

coordination

Table

were

All

DISCUSSION

summarized

Some

T-800

elsewhere

The

were

rrere Coherent

grating (DDR)

RESULTS

are

Model

ion lasers.'

Zeiss

12 or

measurements

sources

holographic Carl

solutions system.

a silicon-windowed

routines

Raman

a Coderg light

i-r.

approximately

-and subtraction

The

of-aqueous

transform

H20

461

Chlorides 962.5

d

vse

vsf

U02

asymmetric

956 222

w,b

UC1

stretch

UO3

stretches

Nitrates 148Ow,

1327p,

1037~

neither U02

,245m

(8725,~)

1538vs,

1468~s 1390m

930s,sh,

i

1144w,sh,

1047s

NO;

monodentate

86Ow,

261s

a Ran-an frequencies mol

are

dm O3 solution

UO,(ClO,),

+ LiCl;

or CS[UO~(NO~>~ (20°C)

CO

stretches

of bidentate

CO

stretches

of monodentate

SO stretches

208w,b

tion

nor

stretch

UO2 asymmetric

919vs

Sulphates

' 0.1

of coordinated

bidentate

h

Acetates

956vs,

[U02C1]'

modes

U-NO3

191w

1603m,

of

g 1409w,m,

961vs,

stretch

modes stretch

1 mol

dm-3

i-r.

of U02(02CCH3)2;

=

1:l;

of monodentate

of oxyanion

solution

' 0.5

mol

~~5 dm

NaN03 solution

for

[SO4]-

ligand

of U02(C104)2;

; d 1 mol dme3 uranium ’ U:Cl = 1:8; g 1 mol dme3

and_U02(C104)2

acetate

stretches

of Na3(U02F5]

e U:Cl

] for

b

in brackets;

U02 U-O

acetate

concentration

solhution

Ramn;

from

of U02(N03)2

Saturated

solu-

of U02S04.

REFERENCES 1 2 3 4

C.Carr and P.L. Goggin, J.Mol.Struct., 79 (1983) 261-265. P.L.Goggin, M.G?il and J-Mink, manuscript in preparation. M.M.Brooker, C-H. Huang and J.Sylwestrowicz, J.Inorg.Nucl.Chem., 1431-1440. L-H-Jones, Spectrochim.Acta 15 (1959) 409-411.

42

(1980)

STRETCH V3 962.5

STRETCH VI 874 871.5+ 872 866.5

-u0,(c104),

[U02(N03)jRb

uo2(No3)2

uo2c12

u"2F2

835 827

IUo2F5]Naq 908

(9'6)

919x

927

920.5*

262*

270*

261

268*

260

254

254

V2 253

u"P BENDING

6.646

6.770

6.776

6.925

6.835

7.063

7.281

!.292

7.333

7.418

7.414

.

K(UO)

-0.202

-0.200

-0.238

-0.213

-0.202

-0.199

-0.311

-0.110

-0.259

-0.254

-0.257

0.248

K(UO,UO)

0.285

0.303

0.283

0.298

0.281

0.268

0.268

.

H(OU0)

174.4

174.1

174.1

173.7

173.6

173.3

172.7

172.7

172,6

172.4

172.4

172.2

R(U0)' (pm)

* CALCULATED BY EXPRESSION OF REF.[4]

IN BRACKETS PREDICTED VALUES CALCULATED BY V, = 0.795 V3 - 107

+ FROM RAMAN SPECTRUM OF Cs SALT; * CH2C'12SOLUTION DATA; ** H20 SOLUTION OF U02(C104)t5 Li(O2CCH3);

833"

[Uo2F51[NH413

844

hJo2C141[N(C4Hg)4] 2

UO,(O,CCH,),**

[U02(02CCH,)~[N(C3H7)4](839)

956

860 853.5

uo2s04 (939)

944*

[uo,(No,),][N(C,~~,)~]873,862*

(956)

961

961

U02ASYM.

U02SYM.

COMPOUNDS

TABLE 2 : URANYL MODES (cm-') AND FORCE CONSTANTS (N cm-') OF SOLVATED URANYL ION

.