Local Electronic Structure in AlN Studied by Single-Crystal <sup>27</sup>Al and <sup>14</sup>N NMR and DFT Calculations
Both the chemical shift and quadrupole coupling tensors for <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>14</mn> </msup> </semantics> </math> </inline-formula>N and <inline-formula&g...
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2020-01-01
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| Online Access: | https://www.mdpi.com/1420-3049/25/3/469 |
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doaj-8ca46d3ce77146fa8c7422b0beb619e1 |
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Article |
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DOAJ |
| language |
English |
| format |
Article |
| sources |
DOAJ |
| author |
Otto E. O. Zeman Igor L. Moudrakovski Carsten Hartmann Sylvio Indris Thomas Bräuniger |
| spellingShingle |
Otto E. O. Zeman Igor L. Moudrakovski Carsten Hartmann Sylvio Indris Thomas Bräuniger Local Electronic Structure in AlN Studied by Single-Crystal <sup>27</sup>Al and <sup>14</sup>N NMR and DFT Calculations Molecules aln single-crystal nmr <sup>14</sup>n nmr <sup>27</sup>al nmr chemical shift tensor quadrupole coupling tensor |
| author_facet |
Otto E. O. Zeman Igor L. Moudrakovski Carsten Hartmann Sylvio Indris Thomas Bräuniger |
| author_sort |
Otto E. O. Zeman |
| title |
Local Electronic Structure in AlN Studied by Single-Crystal <sup>27</sup>Al and <sup>14</sup>N NMR and DFT Calculations |
| title_short |
Local Electronic Structure in AlN Studied by Single-Crystal <sup>27</sup>Al and <sup>14</sup>N NMR and DFT Calculations |
| title_full |
Local Electronic Structure in AlN Studied by Single-Crystal <sup>27</sup>Al and <sup>14</sup>N NMR and DFT Calculations |
| title_fullStr |
Local Electronic Structure in AlN Studied by Single-Crystal <sup>27</sup>Al and <sup>14</sup>N NMR and DFT Calculations |
| title_full_unstemmed |
Local Electronic Structure in AlN Studied by Single-Crystal <sup>27</sup>Al and <sup>14</sup>N NMR and DFT Calculations |
| title_sort |
local electronic structure in aln studied by single-crystal <sup>27</sup>al and <sup>14</sup>n nmr and dft calculations |
| publisher |
MDPI AG |
| series |
Molecules |
| issn |
1420-3049 |
| publishDate |
2020-01-01 |
| description |
Both the chemical shift and quadrupole coupling tensors for <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>14</mn> </msup> </semantics> </math> </inline-formula>N and <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>27</mn> </msup> </semantics> </math> </inline-formula>Al in the wurtzite structure of aluminum nitride have been determined to high precision by single-crystal NMR spectroscopy. A homoepitaxially grown AlN single crystal with known morphology was used, which allowed for optical alignment of the crystal on the goniometer axis. From the analysis of the rotation patterns of <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>14</mn> </msup> </semantics> </math> </inline-formula>N (<inline-formula> <math display="inline"> <semantics> <mrow> <mi>I</mi> <mo>=</mo> <mn>1</mn> </mrow> </semantics> </math> </inline-formula>) and <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>27</mn> </msup> </semantics> </math> </inline-formula>Al (<inline-formula> <math display="inline"> <semantics> <mrow> <mi>I</mi> <mo>=</mo> <mn>5</mn> <mo>/</mo> <mn>2</mn> </mrow> </semantics> </math> </inline-formula>), the quadrupolar coupling constants were determined to <inline-formula> <math display="inline"> <semantics> <mrow> <mi>χ</mi> <mrow> <msup> <mo>(</mo> <mn>14</mn> </msup> <mi mathvariant="normal">N</mi> <mo>)</mo> </mrow> <mo>=</mo> <mrow> <mo>(</mo> <mn>8.19</mn> <mo>±</mo> <mn>0.02</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> kHz, and <inline-formula> <math display="inline"> <semantics> <mrow> <mi>χ</mi> <mrow> <msup> <mo>(</mo> <mn>27</mn> </msup> <mi>Al</mi> <mo>)</mo> </mrow> <mo>=</mo> <mrow> <mo>(</mo> <mn>1.914</mn> <mo>±</mo> <mn>0.001</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> MHz. The chemical shift parameters obtained from the data fit were <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mi>δ</mi> <mrow> <mi>i</mi> <mi>s</mi> <mi>o</mi> </mrow> </msub> <mo>=</mo> <mo>−</mo> <mrow> <mo>(</mo> <mn>292.6</mn> <mo>±</mo> <mn>0.6</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> ppm and <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mi>δ</mi> <mo>Δ</mo> </msub> <mo>=</mo> <mo>−</mo> <mrow> <mo>(</mo> <mn>1.9</mn> <mo>±</mo> <mn>1.1</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> ppm for <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>14</mn> </msup> </semantics> </math> </inline-formula>N, and (after correcting for the second-order quadrupolar shift) <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mi>δ</mi> <mrow> <mi>i</mi> <mi>s</mi> <mi>o</mi> </mrow> </msub> <mo>=</mo> <mrow> <mo>(</mo> <mn>113.6</mn> <mo>±</mo> <mn>0.3</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> ppm and <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mi>δ</mi> <mo>Δ</mo> </msub> <mo>=</mo> <mrow> <mo>(</mo> <mn>12.7</mn> <mo>±</mo> <mn>0.6</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> ppm for <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>27</mn> </msup> </semantics> </math> </inline-formula>Al. DFT calculations of the NMR parameters for non-optimized crystal geometries of AlN generally did not match the experimental values, whereas optimized geometries came close for <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>27</mn> </msup> </semantics> </math> </inline-formula>Al with <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mover> <mi>χ</mi> <mo>¯</mo> </mover> <mi>calc</mi> </msub> <mo>=</mo> <mrow> <mo>(</mo> <mn>1.791</mn> <mo>±</mo> <mn>0.003</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> MHz, but not for <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>14</mn> </msup> </semantics> </math> </inline-formula>N with <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mover> <mi>χ</mi> <mo>¯</mo> </mover> <mi>calc</mi> </msub> <mo>=</mo> <mo>−</mo> <mrow> <mo>(</mo> <mn>19.5</mn> <mo>±</mo> <mn>3.3</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> kHz. |
| topic |
aln single-crystal nmr <sup>14</sup>n nmr <sup>27</sup>al nmr chemical shift tensor quadrupole coupling tensor |
| url |
https://www.mdpi.com/1420-3049/25/3/469 |
| work_keys_str_mv |
AT ottoeozeman localelectronicstructureinalnstudiedbysinglecrystalsup27supalandsup14supnnmranddftcalculations AT igorlmoudrakovski localelectronicstructureinalnstudiedbysinglecrystalsup27supalandsup14supnnmranddftcalculations AT carstenhartmann localelectronicstructureinalnstudiedbysinglecrystalsup27supalandsup14supnnmranddftcalculations AT sylvioindris localelectronicstructureinalnstudiedbysinglecrystalsup27supalandsup14supnnmranddftcalculations AT thomasbrauniger localelectronicstructureinalnstudiedbysinglecrystalsup27supalandsup14supnnmranddftcalculations |
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1725164206926331904 |
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doaj-8ca46d3ce77146fa8c7422b0beb619e12020-11-25T01:12:57ZengMDPI AGMolecules1420-30492020-01-0125346910.3390/molecules25030469molecules25030469Local Electronic Structure in AlN Studied by Single-Crystal <sup>27</sup>Al and <sup>14</sup>N NMR and DFT CalculationsOtto E. O. Zeman0Igor L. Moudrakovski1Carsten Hartmann2Sylvio Indris3Thomas Bräuniger4Department of Chemistry, University of Munich (LMU), Butenandtstr. 5-13, 81377 Munich, GermanyMax-Planck-Institut for Solid-State Research, Heisenbergstrasse 1, 70569 Stuttgart, GermanyLeibniz-Institut für Kristallzüchtung (IKZ), Max-Born-Str. 2, 12489 Berlin, GermanyKarlsruhe Institute of Technology, Institute for Applied Materials (IAM), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, GermanyDepartment of Chemistry, University of Munich (LMU), Butenandtstr. 5-13, 81377 Munich, GermanyBoth the chemical shift and quadrupole coupling tensors for <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>14</mn> </msup> </semantics> </math> </inline-formula>N and <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>27</mn> </msup> </semantics> </math> </inline-formula>Al in the wurtzite structure of aluminum nitride have been determined to high precision by single-crystal NMR spectroscopy. A homoepitaxially grown AlN single crystal with known morphology was used, which allowed for optical alignment of the crystal on the goniometer axis. From the analysis of the rotation patterns of <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>14</mn> </msup> </semantics> </math> </inline-formula>N (<inline-formula> <math display="inline"> <semantics> <mrow> <mi>I</mi> <mo>=</mo> <mn>1</mn> </mrow> </semantics> </math> </inline-formula>) and <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>27</mn> </msup> </semantics> </math> </inline-formula>Al (<inline-formula> <math display="inline"> <semantics> <mrow> <mi>I</mi> <mo>=</mo> <mn>5</mn> <mo>/</mo> <mn>2</mn> </mrow> </semantics> </math> </inline-formula>), the quadrupolar coupling constants were determined to <inline-formula> <math display="inline"> <semantics> <mrow> <mi>χ</mi> <mrow> <msup> <mo>(</mo> <mn>14</mn> </msup> <mi mathvariant="normal">N</mi> <mo>)</mo> </mrow> <mo>=</mo> <mrow> <mo>(</mo> <mn>8.19</mn> <mo>±</mo> <mn>0.02</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> kHz, and <inline-formula> <math display="inline"> <semantics> <mrow> <mi>χ</mi> <mrow> <msup> <mo>(</mo> <mn>27</mn> </msup> <mi>Al</mi> <mo>)</mo> </mrow> <mo>=</mo> <mrow> <mo>(</mo> <mn>1.914</mn> <mo>±</mo> <mn>0.001</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> MHz. The chemical shift parameters obtained from the data fit were <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mi>δ</mi> <mrow> <mi>i</mi> <mi>s</mi> <mi>o</mi> </mrow> </msub> <mo>=</mo> <mo>−</mo> <mrow> <mo>(</mo> <mn>292.6</mn> <mo>±</mo> <mn>0.6</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> ppm and <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mi>δ</mi> <mo>Δ</mo> </msub> <mo>=</mo> <mo>−</mo> <mrow> <mo>(</mo> <mn>1.9</mn> <mo>±</mo> <mn>1.1</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> ppm for <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>14</mn> </msup> </semantics> </math> </inline-formula>N, and (after correcting for the second-order quadrupolar shift) <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mi>δ</mi> <mrow> <mi>i</mi> <mi>s</mi> <mi>o</mi> </mrow> </msub> <mo>=</mo> <mrow> <mo>(</mo> <mn>113.6</mn> <mo>±</mo> <mn>0.3</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> ppm and <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mi>δ</mi> <mo>Δ</mo> </msub> <mo>=</mo> <mrow> <mo>(</mo> <mn>12.7</mn> <mo>±</mo> <mn>0.6</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> ppm for <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>27</mn> </msup> </semantics> </math> </inline-formula>Al. DFT calculations of the NMR parameters for non-optimized crystal geometries of AlN generally did not match the experimental values, whereas optimized geometries came close for <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>27</mn> </msup> </semantics> </math> </inline-formula>Al with <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mover> <mi>χ</mi> <mo>¯</mo> </mover> <mi>calc</mi> </msub> <mo>=</mo> <mrow> <mo>(</mo> <mn>1.791</mn> <mo>±</mo> <mn>0.003</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> MHz, but not for <inline-formula> <math display="inline"> <semantics> <msup> <mrow></mrow> <mn>14</mn> </msup> </semantics> </math> </inline-formula>N with <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mover> <mi>χ</mi> <mo>¯</mo> </mover> <mi>calc</mi> </msub> <mo>=</mo> <mo>−</mo> <mrow> <mo>(</mo> <mn>19.5</mn> <mo>±</mo> <mn>3.3</mn> <mo>)</mo> </mrow> </mrow> </semantics> </math> </inline-formula> kHz.https://www.mdpi.com/1420-3049/25/3/469alnsingle-crystal nmr<sup>14</sup>n nmr<sup>27</sup>al nmrchemical shift tensorquadrupole coupling tensor |