The crystal structure of solvent-free Li_2B_(12)H_(12) has been determined by powder X-ray diffraction and confirmed by a combination of neutron vibrational spectroscopy and first-principles calculations. This compound is a possible intermediate in the dehydrogenation of LiBH_4, and its structural characterization is crucial for understanding the decomposition and regeneration of LiBH_4. Our results reveal that the structure of Li_2B_(12)H_(12) differs from other known alkali-metal (K, Rb, and Cs) derivatives

Bowman, Robert C., Jr.

Her, Jae-Hyuk

Hwang, Son-Jong

Jalisatgi, Satish S.

Kulleck, James G.

Udovic, Terrence J.

Yousufuddin, Muhammed

Zan, Jason A.

Zhou, Wei

English

Caltech Authors - Main

 
 
 
 
 
 
Supporting Information for: 
 
 
 
Crystal Structure of Li2B12H12: a Possible Intermediate Species in the 
Decomposition of LiBH4  
 
Jae-Hyuk Her1,2*, Muhammed Yousufuddin1,2, Wei Zhou1,2, Satish S. Jalisatgi3, James G. 
Kulleck4, Jason A. Zan4, Son-Jong Hwang5, Robert C. Bowman4, Jr., and Terrence J. 
Udovic1  
1
NIST Center for Neutron Research, National Institute of Standards and Technology, 100 Bureau Drive, MD 
20899-6102, 
2
Department of Materials Science and Engineering, University of Maryland, College Park, MD 
20742-2115, 
3
International Institute of Nano and Molecular Medicine, Department of Radiology, 201 
Chemistry Bldg. Columbia, MO 65211, 
4
Jet Propulsion Laboratory, California Institute of Technology, 
Pasadena, California 91109, 5Division of Chemistry and Chemical Engineering, California Institute of 
Technology, Pasadena, CA 91125-4100   
 
 
 
 
Inorg Chem. 
The XRD data were collected at room temperature with a Rigaku Ultra III* sealed 
tube (1.6 kW, Cu Kα) diffractometer.  The TOPAS-Academic* program was used to index 
the pattern and to solve and refine the structure. The crystal structure was solved by the 
direct space searching method (simulated annealing).  An ideal dodecahedron rigid body 
was defined for the B12H12
2- anion, and dynamic occupancy correction was enabled during 
the annealing process.  After decent agreement was achieved between observed and 
calculated patterns, the structure model was trimmed out by removing duplicated atoms in 
the rigid-body definition due to the incorporation of molecular and crystallographic 
symmetry operations and taking into account the special position requirement.  The 
Rietveld refinement was still done with a rigid-body model since the powder pattern did not 
contain enough information to localize the individual atomic positions, especially due to the 
insensitivity of x-rays for H atoms.  Though the B and H atoms were constrained, the B-B 
and B-H distances were allowed to vary.  All displacement parameters were treated 
isotropically, and all like atoms were constrained to the same values.  
First-principles calculations were performed within the plane-wave implementation 
of the generalized gradient approximation to density functional theory (DFT) using the 
PWscf package* (Baroni, S.; Dal Corso, A.; de Gironcoli, S.; Giannozzi, P. 
http://www.pwscf.org). We used a Vanderbilt-type ultrasoft potential with Perdew-Burke-
Ernzerhof exchange correlation.  A cutoff energy of 400 eV and a 4×4×4 k-point mesh 
were found to be enough for the total energy to converge within 0.5 meV/atom and 5 
meV/Å. 
The neutron vibrational spectrum for Li2B12H12 at 4 K was measured at the 
National Institute of Standards and Technology Center for Neutron Research with the BT-4 
Filter Analyzer Neutron Spectrometer using horizontal 20' collimations before and after the 
Cu(220) monochromator.
                                            
*Certain commercial suppliers are identified in this paper to foster understanding. Such identification does not 
imply recommendation or endorsement by the NIST nor does it imply that the materials, equipment, or 
software identified are necessarily the best available for the purpose. 
 
 
Table S1.  Experimental and crystallographic details. 
Crystal data  
Chemical formula Li2B12H12 
Mr 155.70 
Cell setting, space group Cubic, Pa3
_
 
Data collection temperature Ambient 
a, b, c (Å) 9.5771(2), 9.5771(2), 9.5771(2) 
α, β, γ (°) 90, 90, 90 
Volume (Å3) 878.43(6) 
Z 4 
Dx (Mg m
-3) 1.17747(8) 
Radiation type Cu Kα 
Specimen color White 
  
Refinement  
Refinement method Rietveld 
R factors and goodness-of-fit Rp = 0.038, Rwp = 0.050, Rexp = 0.032, RB = 0.008, S = 1.563 
Number of parameters 38 
H-atom treatment Rigid body (dodecahedron) 
Weighting scheme 1/σ2 
(∆/σ)max <0.001 
  
Result  
Li-H distances (Å) 2.077(7), 2.216(7) 
B-H distance (Å) 1.205(13) 
B-B distances (Å) 1.7800(32), 1.7984(14), 1.8002(16), 1.8034(24), 1.8102(32) 
Li thermal parameter 4.7(2) 
B, H thermal parameter 1.98(7) 
 


Crystal structure of Li_2B_(12)H_(12): a possible intermediate species in the decomposition of LiBH_4

  
 
 
 
 
Supporting Information for: 
 
 
 
Crystal Structure of Li2B12H12: a Possible Intermediate Species in the 
Decomposition of LiBH4  
 
Jae-Hyuk Her1,2*, Muhammed Yousufuddin1,2, Wei Zhou1,2, Satish S. Jalisatgi3, James G. 
Kulleck4, Jason A. Zan4, Son-Jong Hwang5, Robert C. Bowman4, Jr., and Terrence J. 
Udovic1  
1NIST Center for Neutron Research, National Institute of Standards and Technology, 100 Bureau Drive, MD 
20899-6102, 2Department of Materials Science and Engineering, University of Maryland, College Park, MD 
20742-2115, 3International Institute of Nano and Molecular Medicine, Department of Radiology, 201 
Chemistry Bldg. Columbia, MO 65211, 4Jet Propulsion Laboratory, California Institute of Technology, 
Pasadena, California 91109, 5Division of Chemistry and Chemical Engineering, California Institute of 
Technology, Pasadena, CA 91125-4100   
 
 
 
 
Inorg Chem. 
The XRD data were collected at room temperature with a Rigaku Ultra III* sealed 
tube (1.6 kW, Cu Kα) diffractometer.  The TOPAS-Academic* program was used to index 
the pattern and to solve and refine the structure. The crystal structure was solved by the 
direct space searching method (simulated annealing).  An ideal dodecahedron rigid body 
was defined for the B12H122- anion, and dynamic occupancy correction was enabled during 
the annealing process.  After decent agreement was achieved between observed and 
calculated patterns, the structure model was trimmed out by removing duplicated atoms in 
the rigid-body definition due to the incorporation of molecular and crystallographic 
symmetry operations and taking into account the special position requirement.  The 
Rietveld refinement was still done with a rigid-body model since the powder pattern did not 
contain enough information to localize the individual atomic positions, especially due to the 
insensitivity of x-rays for H atoms.  Though the B and H atoms were constrained, the B-B 
and B-H distances were allowed to vary.  All displacement parameters were treated 
isotropically, and all like atoms were constrained to the same values.  
First-principles calculations were performed within the plane-wave implementation 
of the generalized gradient approximation to density functional theory (DFT) using the 
PWscf package* (Baroni, S.; Dal Corso, A.; de Gironcoli, S.; Giannozzi, P. 
http://www.pwscf.org). We used a Vanderbilt-type ultrasoft potential with Perdew-Burke-
Ernzerhof exchange correlation.  A cutoff energy of 400 eV and a 4×4×4 k-point mesh 
were found to be enough for the total energy to converge within 0.5 meV/atom and 5 
meV/Å. 
The neutron vibrational spectrum for Li2B12H12 at 4 K was measured at the 
National Institute of Standards and Technology Center for Neutron Research with the BT-4 
Filter Analyzer Neutron Spectrometer using horizontal 20' collimations before and after the 
Cu(220) monochromator.
                                            
*Certain commercial suppliers are identified in this paper to foster understanding. Such identification does not 
imply recommendation or endorsement by the NIST nor does it imply that the materials, equipment, or 
software identified are necessarily the best available for the purpose. 
  
Table S1.  Experimental and crystallographic details. 
Crystal data  
Chemical formula Li2B12H12 
Mr 155.70 
Cell setting, space group Cubic, Pa3
_
 
Data collection temperature Ambient 
a, b, c (Å) 9.5771(2), 9.5771(2), 9.5771(2) 
α, β, γ (°) 90, 90, 90 
Volume (Å3) 878.43(6) 
Z 4 
Dx (Mg m-3) 1.17747(8) 
Radiation type Cu Kα 
Specimen color White 
  
Refinement  
Refinement method Rietveld 
R factors and goodness-of-fit Rp = 0.038, Rwp = 0.050, Rexp = 0.032, RB = 0.008, S = 1.563 
Number of parameters 38 
H-atom treatment Rigid body (dodecahedron) 
Weighting scheme 1/σ2 
(∆/σ)max <0.001 
  
Result  
Li-H distances (Å) 2.077(7), 2.216(7) 
B-H distance (Å) 1.205(13) 
B-B distances (Å) 1.7800(32), 1.7984(14), 1.8002(16), 1.8034(24), 1.8102(32) 
Li thermal parameter 4.7(2) 
B, H thermal parameter 1.98(7) 
 


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Crystal structure of Li_2B_(12)H_(12): a possible intermediate species in the decomposition of LiBH_4

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