Supporting Information
An elegant room temperature procedure for the precise control
of composition in the Cu-S system
Prashant Kumar and R. Nagarajan*
Materials Chemistry Group, Department of Chemistry, University of Delhi, Delhi 110007
INDIA
Experimental Procedure and Characterizations Details
Synthetic procedure for CuCl:
To a solution of CuCl2.2H2O (Fisher Scientific, AR grade) in 10 ml H2O, a 50 ml solution containing 7.6 g anhydrous Na2SO3 (SRL, India, AR grade) was added slowly. The solution became
dark brown first and then turned white and finally, the white colored CuCl precipitated after the
addition of Na2SO3 solution was completed. The precipitate and supernatant liquid was then
poured in 1 liter of water (consisting of 1 g of Na2SO3 and 2 mL of conc. HCl), stirred well and
allowed to stand until all the CuCl settled down The supernatant liquid was carefully decanted
and the precipitate was quickly washed with dil. sulfurous acid followed by 10-15 mL of glacial
acetic acid, 15 mL of absolute alcohol and 10 mL anhydrous diethyl ether. The white solid was
immediately transferred to a previously dried watch glass. It was preserved in air tight bottle.
Synthetic procedure for [Cu(tu)3]Cl
[Cu(tu)3]Cl complex was obtained by dissolving 99 mg (1 mmol) of freshly prepared CuCl in
5mL aqueous solution of thiourea (SRL, India, AR Grade) (228.4 mg, 3 mmol) stepwise and stirring for 30 minutes. The solution was filtered off and crystallized at room temperature naturally.
1
To get the sufficient quantity of copper thiourea chloride complex, the reaction was repeated in
several batches.
Preparation of Cu2S from [Cu(tu)3]Cl
To prepare Cu2S, 2 g of [Cu(tu)3]Cl was added to 30mL of ethylenediamine (Thomas
Baker, AR grade) taken in a 100 mL round bottom flask and stirred magnetically for 12 h. After
the reaction, the black colored solid was vacuum filtered and washed several times with double
distilled water, ethanol and carbon disulfide. Filtered product was dried naturally at room temperature and characterized thoroughly. To improve the crystallinity of the sample, reactions were
also conducted under solvothermal conditions at 130°C for 12 h.
Preparation of Cu9S5, Cu7S4, Cu9S8 and CuS from Cu2S by the chemical oxidation procedure
Chemical oxidation experiments were carried out by immersing 0.2 g of solid Cu2S in 20
mL of moisture free acetonitrile in a 100 mL two neck round bottom flask in which the argon gas
was passed throughout the reaction. To synthesize Cu9S5, Cu7S4, Cu9S8 (Cu1.12S), and CuS,
0.0710 g (0.2 mol of I), 0.08 g (0.25 mol of I), 0.3124 g (0.88 mol of I) and 0.3550 g (1 mol of I)
of I2 (Merck, GR grade) were respectively added to 0.2 g Cu2S and the reaction was carried out
for 24-48 h with continuous stirring. After the reaction, the product was washed thoroughly with
dry acetonitrile and dried naturally over a desiccant.
Characterization Details
The phase composition and structure of the final products were determined from the powder Xray diffraction patterns using a Bruker D8 Discover X-ray diffractometer, with Cu Kα1 radiation
(λ = 1.5405 Å) with a scan rate of 1.2 s/step and step size 0.02 at 298 K. Le Bail fitting of the
2
powder X-ray diffraction pattern was carried out using FullProf suite software program.1,2 Raman
spectra of the samples, in compact form, were collected at room temperature using a Renishaw
spectrophotometer equipped with a microscope having laser wavelength of 514 nm. Composition
of Cu2S was measured by measuring the concentration of copper ions in supernatant solutions
using inductively coupled plasma (ICP) spectroscopy with ICP-OES Vista MPS, Varian.
Photoluminescence (PL) measurements were performed on a Horiba Jobin Yvon
Fluorolog 3 Spectrofluorometer at room temperature. Magnetic measurements were carried out at
300 K using a vibrating sample magnetometer (Microsense EV9). The FT-IR spectrum was recorded using Perkin-Elmer 2000 Fourier-Transform infrared spectrometer in the range 400-4000
cm-1 using KBr disks. Thermogravimetric (TG) analysis was carried out using Shimadzu simultaneous TG/DTA thermal analyzer (DTG-60). The samples were heated at the rate of 10°C/min.
C, H, N, and S elemental analysis was carried out using CHNS Elemental Analyzer (PerkinElmer).
References:
1. Le Bail, A.; Duroy, H.; Fourquet, J.L. Mater. Res. Bull. 1988, 23, 447-452.
2. Carvajal, J. R.; Full Prof Suite Program (version 1.00), February 2007, Laboratoire Leon, Brillouin (CEA/CNRS), CEA-Saclay, 91191, Gifsur-Yvette, Cedex, France.
3
Table S1 C, H, N, and S elemental analysis of [Cu(tu)3]Cl.
Elements
[Cu(tu)3]Cl
Theoretical Experimental
(%)
(%)
Carbon
11.01
Hydrogen 3.66
11.03
3.652
Nitrogen
25.68
25.63
Sulfur
29.35
29.28
4
Table S2 Comparison of the FT-IR band positions of thiourea and [Cu(tu)3]Cl.
Thiourea (tu)
[Cu(tu)3]Cl
(cm-1)
(cm-1)
3411 (s, br)
3467 (w)
3259 (s, br)
3160 (s, br)
2929 (w, s)
2683 (w,br)
2683 (w, br)
2369,2330 (w, br)
2100,2039
(w,br)
1623 (s, br)
1605 (s)
1465 (s, br)
1474 (w)
1406 (w, br)
1426,1390 (s)
1088 (w, br)
1088 (w, br)
727 (s, br)
713 (w)
618 (s, br)
592 (w,br)
495 (w, br)
472 (s)
5
Figure S1 Raman spectrum of [Cu(tu)3]Cl.
6
Figure S2 Thermogravimetric trace of [Cu(tu)3]Cl in air.
7
Figure S3 Photoluminescence spectra of Cu9S5, Cu9S8 and CuS when excited with λex = 380 nm
at room temperature.
8
(b)
(a)
(c)
(d)
Figure S4 Plot of magnetization versus magnetic field for (a) Cu2S (b) Cu9S5 (c) Cu9S8 and (d)
CuS at room temperature.
9
##############################################################################
###
FullProf-generated CIF output file (version: February 2008)
###
Template of CIF submission form for structure report
###
###
##############################################################################
#====================================================================
=========
POWDER SPECIMEN AND CRYSTAL DATA
symmetry_cell_setting
Monoclinic
symmetry_space_group_name_H-M
'P 21/c'
symmetry_space_group_name_Hall
'-P 2ybc'
symmetry_equiv_pos_as_xyz #<--must include 'x,y,z'
'x,y,z'
'-x,y+1/2,-z+1/2'
'-x,-y,-z'
'x,-y+1/2,z+1/2'
_cell_length_a
15.1300(16)
_cell_length_b
11.8447(9)
_cell_length_c
13.5047(20)
_cell_angle_alpha
90.00000
_cell_angle_beta
115.923(7)
_cell_angle_gamma
_cell_volume
90.00000
2176.7(4)
_cell_formula_units_Z
#====================================================================
========= EXPERIMENTAL DATA
_diffrn_ambient_temperature
_diffrn_source
_diffrn_radiation_type
298 K
X-ray tube'
'X-ray'
10
_diffrn_source_target
CuK
_pd_meas_number_of_points
3001
_pd_meas_2theta_range_min
10.00000
_pd_meas_2theta_range_max
70.00000
_pd_meas_2theta_range_inc
0.020000
#====================================================================
=========
REFINEMENT DATA
_pd_proc_ls_prof_R_factor
7.3307
_pd_proc_ls_prof_wR_factor
10.5231
_pd_proc_ls_prof_wR_expected
5.4441
# The following profile R-factors are CORRECTED for background
# The sum is extended to all non-excluded points.
# These items are not in the current CIF standard, but are defined above
_pd_proc_ls_prof_cR_factor
17.4739
_pd_proc_ls_prof_cwR_factor
21.0047
_pd_proc_ls_prof_cwR_expected
10.8667
# The following items are not in the CIF standard, but are defined above
_pd_proc_ls_prof_chi2
3.7363
_pd_proc_ls_prof_echi2
3.7363
# Items related to LS refinement
_refine_ls_R_I_factor
_refine_ls_number_reflns
_refine_ls_number_parameters
2.0104
1814
6
11
_refine_ls_number_restraints
0
# The following four items apply to angular dispersive measurements.
# 2theta minimum, maximum and increment (in degrees) are for the
# intensities used in the refinement.
_pd_proc_2theta_range_min
10.0049
_pd_proc_2theta_range_max
70.0049
_pd_proc_2theta_range_inc
_pd_proc_wavelength
0.020000
1.540560
**********************************************************
** PROGRAM FullProf.2k (Version 5.00 - Jan2011-ILL JRC) **
**********************************************************
M U L T I -- P A T T E R N
Rietveld, Profile Matching & Integrated Intensity
Refinement of X-ray and/or Neutron Data
=> PCR file code: Cu2S
=> DAT file code: Cu2S.dat
-> Relative contribution: 1.0000
==> CONDITIONS OF THIS RUN FOR PATTERN No.: 1
=> Global Refinement of X-ray powder diffraction data
=> Global Refinement of X-ray powder diffraction data
Bragg-Brentano or Debye-Scherrer geometry
=> Title: Cu2S
=> Number of phases:
1
=> Number of excluded regions:
1
=> Number of scattering factors supplied:
0
=> Conventional weights: w=1.0/Variance(yobs)
=> Asymmetry correction as in J.Appl.Cryst. 26,128(1993)
=> Background refined by polynomial function
=> The 5th default profile function was selected
=> Pseudo-Voigt function (ETA variable)
12
X-parameter corresponds to: ETA=ETA0+X*2theta
pV(x)= ETA*L(x)+(1-ETA)*G(x)
==> INPUT/OUTPUT OPTIONS:
=> Generate file *.PRF for plot
=> Output Integrated Intensities
=> Generate new input file *.PCR
=> Data supplied in free format for pattern: 1
=> Plot pattern at each cycle
=> Wavelengths: 1.54056 1.54439
=> Alpha2/Alpha1 ratio: 0.5000
=> Cos(Monochromator angle)= 0.9100
=> Asymmetry correction for angles lower than
0.000 degrees
=> Absorption correction (AC), muR-eff = 0.0000
=> Base of peaks: 2.0*HW*
=> Number of cycles:
8.00
5
=> Relaxation factors ==> for coordinates: 1.00
=> for anisotropic temperature factors: 1.00
=> for halfwidth/strain/size parameters: 1.00
=> for lattice constants and propagation vectors: 1.00
=> EPS-value for convergence:
0.1
=> Number of Least-Squares parameters varied:
6
=>-------> PATTERN number: 1
=> Global parameters and codes ==>
=> Zero-point:
-0.0049
0.0000
=> Background parameters and codes ==>
=> Origin of polynomial at 2theta/TOF/E(KeV): 40.000
233.24
0.00
48.430
0.00
-484.76
0.00
-620.38
0.00
905.26
0.00
895.48
0.00
=> Displacement peak-shift parameter and code:
-0.17 11.00
=> Transparency peak-shift parameter and code:
-0.01
0.00
==> Angular range, step and number of points:
13
2Th min:
10.000000 2Th
max:
70.000000 Step:
0.020000 No. of points: 3001
-------------------------------------------------------------------------------=> Phase No. 1 monoclinic
------------------------------------------------------------------------------=>-------> Pattern# 1
=> Profile Matching (fixed scale)
=> Input data if irf=2: Integrated Intensities
=> Preferred orientation vector: 0.0000 0.0000 1.0000
=> Data for PHASE: 1
=> Number of atoms:
0
=> Number of distance constraints:
=> Number of angle constraints:
0
0
=> Symmetry information on space group: P 21/c
-> The multiplicity of the general position is: 4
-> The space group is Centric (-1 at origin)
-> Lattice type P: {000}
-> Reduced set of symmetry operators:
No. IT Symmetry symbol
1: (1) 1
-->
Rotation part
Associated Translation
(x, y, z) + {0.0000 0.0000 0.0000}
2: (3) 2 (0, y, 0) -->
(-x, y,-z) + {0.0000 0.5000 0.5000}
Information on Space Group:
--------------------------=> Number of Space group: 14
=> Hermann-Mauguin Symbol: P 21/c
=> Hall Symbol: -P 2ybc
=> Table Setting Choice: b1
=> Setting Type: IT (Generated from Hermann-Mauguin symbol)
=>
Crystal System: Monoclinic
=>
Laue Class: 2/m
=>
Point Group: 2/m
=>
Bravais Lattice: P
14
=>
Lattice Symbol: mP
=> Reduced Number of S.O.: 2
=> General multiplicity: 4
=>
Centrosymmetry: Centric (-1 at origin)
=> Generators (exc. -1&L): 1
=>
Asymmetric unit: 0.000 <= x <= 1.000
0.000 <= y <= 0.250
0.000 <= z <= 1.000
=> List of S.O. without inversion and lattice centering translations
=> SYMM (1): x, y, z
=> SYMM (2): -x,y+1/2,-z+1/2
=>-------> PROFILE PARAMETERS FOR PATTERN: 1
=> Overall scale factor:
1.00000
=> ETA (p-Voigt) OR M (Pearson VII): -0.1458
=> Overall temperature factor:
0.00000
=> Half width U, V, W:
0.10895
0.02089
=> X and Y parameters:
0.0186
0.0000
0.01920
=> Direct cell parameters: 15.1303 11.8443 13.5042 90.0000 115.9260 90.0000
=> Preferred orientation parameters: 0.0000 0.0000
=> Asymmetry parameters
:
0.00000
0.00000
=> Strain parameters
:
0.00000
0.00000
=> Size parameters
:
0.00000
0.00000
0.00000
0.00000
0.00000
==> CODEWORDS FOR PROFILE PARAMETERS of PATTERN# 1
=> Overall scale factor:
0.000
=> ETA (p-Voigt) OR M (Pearson VII):
=> Overall temperature factor:
=> Halfwidth U, V, W:
0.000
0.000
0.000 0.000 0.000
=> X and Y parameters: 31.000 0.000
=> Direct cell parameters: 41.000 51.000 61.000 0.000 21.000 0.000
=> Preferred orientation parameters:
0.000 0.000
=> Asymmetry parameters
:
=> Strain parameters
0.000 0.000 0.000
:
0.000 0.000 0.000 0.000
15
=> Size parameters
:
0.000 0.000
=> Cell constraints according to Laue symmetry: 2/m
Metric information:
=> Direct cell parameters:
a=
15.1303
alpha =
b=
11.8443
90.000 beta =
c=
13.5042
115.926 gamma =
90.000
Direct Cell Volume = 2176.5103
=> Reciprocal cell parameters:
a*=
0.073488
alpha*=
b*=
0.084429
90.000 beta*=
c*=
0.082338
64.074 gamma*=
90.000
Reciprocal Cell Volume = 0.00045945
=> CYCLE No.:
3
------------------------------------------------------------------------------=> Phase 1 Name: monoclinic
==> PROFILE PARAMETERS FOR PATTERN# 1
=> Overall scale factor:
1.000000000
0.000000000
0.000000000
=> Eta(p-Voigt) or m(Pearson VII): -0.145800 0.000000 0.000000
=> Overall tem. factor: 0.000000 0.000000 0.000000
=> Halfwidth parameters:
0.108946 0.000000 0.000000
0.020890 0.000000 0.000000
0.019196 0.000000 0.000000
=> Cell parameters:
15.129977 -0.000109 0.001559
11.844699 0.000099 0.000928
13.504682 0.000126 0.001981
90.000000 0.000000 0.000000
115.923378 -0.000778 0.006675
90.000000 0.000000 0.000000
=> Preferred orientation:
16
0.000000 0.000000 0.000000
0.000000 0.000000 0.000000
=> Asymmetry parameters:
0.000000 0.000000 0.000000
0.000000 0.000000 0.000000
0.000000 0.000000 0.000000
0.000000 0.000000 0.000000
=> X and Y parameters:
0.018646 0.000019 0.000274
0.000000 0.000000 0.000000
=> Strain parameters:
0.000000 0.000000 0.000000
0.000000 0.000000 0.000000
0.000000 0.000000 0.000000
=> Size parameters (G,L):
0.000000 0.000000 0.000000
0.000000 0.000000 0.000000
==> GLOBAL PARAMETERS FOR PATTERN# 1
=> Zero-point:
-0.0049
0.0000
0.0000
=> Background Polynomial Parameters ==>
233.24
0.0000
0.0000
48.430
0.0000
0.0000
-484.76
0.0000
0.0000
-620.38
0.0000
0.0000
905.26
0.0000
0.0000
895.48
0.0000
0.0000
=> Cos( theta)-shift parameter : -0.1691 0.0000 0.0041
=> Sin(2theta)-shift parameter : -0.0071 0.0000 0.0000
17
==> RELIABILITY FACTORS WITH ALL NON-EXCLUDED POINTS FOR PATTERN: 1
=> R-Factors: 7.33
=> Expected :
10.5
Chi2: 3.74
DW-Stat.: 0.5747 Patt#: 1
5.44
=> Deviance : 0.959E+04
=> GoF-index: 1.9
1.8805
Dev*: 3.842
Sqrt(Residual/N)
=> N-P+C: 2494
=> SumYdif
0.6169E+05
SumYobs
SumYcal
0.8415E+06
SumwYobsSQ Residual
0.8419E+06
0.8415E+06
=> Conventional Rietveld Rp,Rwp,Re and Chi2: 17.5
9318.
21.0
10.9
Condition
0.2273E+09
3.736
=> (Values obtained using Ynet, but true sigma(y))
=> SumYnet, Sum(w Ynet**2):
0.3530E+06
0.2112E+06
==> RELIABILITY FACTORS FOR POINTS WITH BRAGG CONTRIBUTIONS FOR
PATTERN: 1
=> R-Factors: 7.33
=> Expected :
10.5
Chi2: 3.74
DW-Stat.: 0.5747 Patt#:
5.44
=> Deviance : 0.959E+04
=> GoF-index: 1.9
1.8805
Dev*: 3.842
Sqrt(Residual/N)
=> N-P+C: 2494
=> SumYdif
0.6169E+05
SumYobs
0.8415E+06
SumYcal
SumwYobsSQ Residual
0.8419E+06
0.8415E+06
=> Conventional Rietveld Rp,Rwp,Re and Chi2: 17.5
9318.
21.0
10.9
Condition
0.2273E+09
3.736
=> (Values obtained using Ynet, but true sigma(y))
=> SumYnet, Sum(w Ynet**2):
0.3530E+06
0.2112E+06
=> Global user-weigthed Chi2 (Bragg contrib.): 3.74
=> ---------> Pattern# 1
18
=> Phase: 1
=> Bragg R-factor: 2.01
=> RF-factor
: 1.22
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+++++++++++
=> CYCLE No.:
3
=> Convergence reached at this CYCLE!!!!
=> Parameter shifts set to zero
------------------------------------------------------------------------------=> Phase 1 Name: monoclinic
-----------------------------------------------------------------------------==> PROFILE PARAMETERS FOR PATTERN# 1
=> Overall scale factor:
1.000000000
0.000000000
0.000000000
=> Eta(p-Voigt) or m(Pearson VII): -0.145800 0.000000 0.000000
=> Overall tem. factor: 0.000000 0.000000 0.000000
=> Halfwidth parameters:
0.108946 0.000000 0.000000
0.020890 0.000000 0.000000
0.019196 0.000000 0.000000
=> Cell parameters:
15.129977 0.000000 0.001559
11.844699 0.000000 0.000928
13.504682 0.000000 0.001981
90.000000 0.000000 0.000000
115.923378 0.000000 0.006675
90.000000 0.000000 0.000000
=> Preferred orientation:
0.000000 0.000000 0.000000
0.000000 0.000000 0.000000
=> Asymmetry parameters:
19
0.000000 0.000000 0.000000
0.000000 0.000000 0.000000
0.000000 0.000000 0.000000
0.000000 0.000000 0.000000
=> X and Y parameters:
0.018646 0.000000 0.000274
0.000000 0.000000 0.000000
=> Strain parameters:
0.000000 0.000000 0.000000
0.000000 0.000000 0.000000
0.000000 0.000000 0.000000
=> Size parameters (G,L):
0.000000 0.000000 0.000000
0.000000 0.000000 0.000000
==> GLOBAL PARAMETERS FOR PATTERN# 1
=> Zero-point:
-0.0049
0.0000
0.0000
=> Background Polynomial Parameters ==>
233.24
0.0000
0.0000
48.430
0.0000
0.0000
-484.76
0.0000
0.0000
-620.38
0.0000
0.0000
905.26
0.0000
0.0000
895.48
0.0000
0.0000
=> Cos( theta)-shift parameter : -0.1691 0.0000 0.0041
=> Sin(2theta)-shift parameter : -0.0071 0.0000 0.0000
==> RELIABILITY FACTORS WITH ALL NON-EXCLUDED POINTS FOR PATTERN: 1
=> R-Factors: 7.33
=> Expected :
10.5
Chi2: 3.74
5.44
=> Deviance : 0.959E+04
DW-Stat.: 0.5747 Patt#: 1
1.8805
Dev*: 3.842
20
=> GoF-index: 1.9
Sqrt(Residual/N)
=> N-P+C: 2494
=> SumYdif
0.6169E+05
SumYobs
SumYcal
0.8415E+06
SumwYobsSQ Residual
0.8419E+06
0.8415E+06
=> Conventional Rietveld Rp,Rwp,Re and Chi2: 17.5
9318.
21.0
10.9
Condition
0.2273E+09
3.736
=> (Values obtained using Ynet, but true sigma(y))
=> SumYnet, Sum(w Ynet**2):
0.3530E+06
0.2112E+06
=> N-sigma of the GoF: 96.626
==> RELIABILITY FACTORS FOR POINTS WITH BRAGG CONTRIBUTIONS FOR
PATTERN: 1
=> R-Factors: 7.33
=> Expected :
10.5
Chi2: 3.74
DW-Stat.: 0.5747 Patt#:
5.44
=> Deviance : 0.959E+04
=> GoF-index: 1.9
1.8805
Dev*: 3.842
Sqrt(Residual/N)
=> N-P+C: 2494
=> SumYdif
0.6169E+05
SumYobs
SumYcal
0.8415E+06
SumwYobsSQ Residual
0.8419E+06
0.8415E+06
=> Conventional Rietveld Rp,Rwp,Re and Chi2: 17.5
9318.
21.0
10.9
Condition
0.2273E+09
3.736
=> (Values obtained using Ynet, but true sigma(y))
=> SumYnet, Sum(w Ynet**2):
=> N-sigma of the GoF:
0.3530E+06
0.2112E+06
96.626
=> Global user-weigthed Chi2 (Bragg contrib.): 3.74
=> ---------> Pattern# 1
=> Phase: 1
=> Bragg R-factor: 2.01
=> RF-factor
: 1.21
21