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論文

In-source laser spectroscopy of dysprosium isotopes at the ISOLDE-RILIS

Chrysalidis, K.*; Barzakh, A. E.*; Ahmed, R.*; Andreyev, A. N.; Ballof, J.*; Cubiss, J. G.*; Fedorov, D. V.*; Fedosseev, V. N.*; Fraile, L. M.*; Harding, R. D.*; et al.

Nuclear Instruments and Methods in Physics Research B, 463, p.472 - 475, 2020/01

 被引用回数:3 パーセンタイル:36.99(Instruments & Instrumentation)

放射壊変によって生成された多数のジスプロシウム同位体について、ISOLDEのレーザー共鳴イオン源(RILIS)を用いてイオン源内レーザー分光法によって研究した。$$^{152}$$Dyに対する相対的な同位体シフトを$$4f^{10}6s^{2}~^{5}I_{8}$$ (gs) $$rightarrow$$ $$4f^{10}6s6p~(8,1)^{o}_{8}$$共鳴遷移を用いて測定した。電子的因子Fとマスシフト因子Mを導出し、それらを使って$$^{rm 145m}$$Dyと$$^{rm 147m}$$Dyの平均自乗荷電半径の変化を初めて決定した。

論文

$$alpha$$-decay branching ratio of $$^{180}$$Pt

Cubiss, J. G.*; Harding, R. D.*; Andreyev, A. N.; Althubiti, N.*; Andel, B.*; Antalic, S.*; Barzakh, A. E.*; Cocolios, T. E.*; Day Goodacre, T.*; Farooq-Smith, G. J.*; et al.

Physical Review C, 101(1), p.014314_1 - 014314_4, 2020/01

 被引用回数:5 パーセンタイル:53.56(Physics, Nuclear)

$$^{180}$$Ptの基底状態から娘核$$^{176}$$Osの基底状態への$$alpha$$崩壊分岐比を0.52(5)%と、過去の値と比較してより高精度で再決定した。$$^{180}$$PtはCERN-ISOLDE実験施設において$$^{180}$$Hgを単離し、その$$beta$$崩壊孫核種として生成した。今回の結果を用いて導出した$$alpha$$崩壊の換算崩壊幅は、中性子欠損Pt同位体の$$alpha$$崩壊幅の系統性について新しい描像を与えることとなった。

論文

A Review of separation processes proposed for advanced fuel cycles based on technology readiness level assessments

Baron, P.*; Cornet, S. M.*; Collins, E. D.*; DeAngelis, G.*; Del Cul, G.*; Fedorov, Y.*; Glatz, J. P.*; Ignatiev, V.*; 井上 正*; Khaperskaya, A.*; et al.

Progress in Nuclear Energy, 117, p.103091_1 - 103091_24, 2019/11

 被引用回数:54 パーセンタイル:93.84(Nuclear Science & Technology)

本論文では、将来のクローズド燃料サイクルにおける使用済燃料のための分離プロセスに対する国際的リビューの結果が、技術成熟度評価の結果ととともに示されている。本研究は、ORCD/NEAで組織された燃料リサイクル化学に関する専門家グループによって実施されたものである。本研究の特徴的な点は、分離プロセスを使用済燃料中の分離対象元素(ウラン, ウラン-プルトニウム, マイナーアクチノイド, 発熱性元素等)別の分離階層により区分けして評価したことであり、これに使用済燃料の前処理プロセスの評価を加えている。分離プロセスとしては湿式プロセスと乾式プロセスの両者をカバーしている。

論文

Fine structure in the $$alpha$$ decay of $$^{218}$$At

Cubiss, J. G.*; Andreyev, A. N.; Barzakh, A. E.*; Andel, B.*; Antalic, S.*; Cocolios, T. E.*; Day Goodacre, T.*; Fedorov, D. V.*; Fedosseev, V. N.*; Ferrer, R.*; et al.

Physical Review C, 99(6), p.064317_1 - 064317_6, 2019/06

 被引用回数:6 パーセンタイル:54.59(Physics, Nuclear)

$$^{218}$$Atの$$alpha$$崩壊について、CERN-ISOLDE施設においてレーザーイオン化法を使うことで研究した。$$alpha$$-$$gamma$$同時計数データを初めて取得し、より精度の良い半減期の値として1.27(6)秒を得た。$$alpha$$崩壊の微細構造を基に新しい$$alpha$$崩壊図式を構築した。それらの結果から、$$^{218}$$Atの基底状態のスピン・パリティは(3$$^{-}$$)がより確からしいことが解ったが、(2)$$^{-}$$の可能性も完全には否定しきれない。

論文

Inverse odd-even staggering in nuclear charge radii and possible octupole collectivity in $$^{217,218,219}$$At revealed by in-source laser spectroscopy

Barzakh, A. E.*; Cubiss, J. G.*; Andreyev, A. N.; Seliverstov, M. D.*; Andel, B.*; Antalic, S.*; Ascher, P.*; Atanasov, D.*; Beck, D.*; Biero$'n$, J.*; et al.

Physical Review C, 99(5), p.054317_1 - 054317_9, 2019/05

 被引用回数:12 パーセンタイル:77.66(Physics, Nuclear)

Hyperfine-structure parameters and isotope shifts for the 795-nm atomic transitions in $$^{217,218,219}$$At have been measured at CERN-ISOLDE, using the in-source resonance-ionization spectroscopy technique. Magnetic dipole and electric quadrupole moments, and changes in the nuclear mean-square charge radii, have been deduced. A large inverse odd-even staggering in radii, which may be associated with the presence of octupole collectivity, has been observed. Namely, the radius of the odd-odd isotope $$^{218}$$At has been found to be larger than the average.

論文

Detailed $$alpha$$-decay study of $$^{180}$$Tl

Andel, B.*; Andreyev, A. N.; Antalic, S.*; Barzakh, A.*; Bree, N.*; Cocolios, T. E.*; Comas, V. F.*; Diriken, J.*; Elseviers, J.*; Fedorov, D. V.*; et al.

Physical Review C, 96(5), p.054327_1 - 054327_11, 2017/12

 被引用回数:3 パーセンタイル:27.8(Physics, Nuclear)

A detailed $$alpha$$-decay spectroscopy study of $$^{180}$$Tl has been performed at ISOLDE (CERN). Z-selective ionization by the Resonance Ionization Laser Ion Source (RILIS) coupled to mass separation provided a high-purity beam of $$^{180}$$Tl. Fine-structure $$alpha$$ decays to excited levels in the daughter $$^{176}$$Au were identified and an $$alpha$$-decay scheme of $$^{180}$$Tl was constructed based on an analysis of $$alpha$$-$$gamma$$ and $$alpha$$-$$gamma$$ -$$gamma$$ coincidences. Multipolarities of several $$gamma$$-ray transitions deexciting levels in $$^{176}$$Au were determined. Based on the analysis of reduced $$alpha$$-decay widths, it was found that all $$alpha$$ decays are hindered, which signifies a change of configuration between the parent and all daughter states.

論文

Changes in mean-squared charge radii and magnetic moments of $$^{179-184}$$Tl measured by in-source laser spectroscopy

Barzakh, A.*; Andreyev, A. N.; Cocolios, T. E.*; de Groote, R. P.*; Fedorov, D. V.*; Fedosseev, V. N.*; Ferrer, R.*; Fink, D. A.*; Ghys, L.*; Huyse, M.*; et al.

Physical Review C, 95(1), p.014324_1 - 014324_12, 2017/01

 被引用回数:22 パーセンタイル:86.87(Physics, Nuclear)

Hyperfine structure and isotope shifts have been measured for the ground and isomeric states in the neutron deficient isotopes $$^{179-184}$$Tl using the 276.9 nm transition. The experiment has been performed at the CERN Isotope Separator On-Line facility using the in-source resonance-ionization laser spectroscopy technique. Spins for the ground states in $$^{179,181,183}$$Tl have been determined as $$I$$ = 1/2. Magnetic moments and changes in the nuclear mean-square charge radii have been deduced. By applying the additivity relation for magnetic moments of the odd-odd Tl nuclei the leading configuration assignments were confirmed. A deviation of magnetic moments for isomeric states in $$^{182,184}$$Tl from the trend of the heavier Tl nuclei is observed. The charge radii of the ground states of the isotopes $$^{179-184}$$Tl follow the trend for isotonic (spherical) lead nuclei. The noticeable difference in charge radii for ground and isomeric states of $$^{183,184}$$Tl has been observed, suggesting a larger deformation for the intruder-based 9/2$$^{-}$$ and 10$$^{-}$$ states compared to the ground states. An unexpected growth of the isomer shift for $$^{183}$$Tl has been found.

論文

$$beta$$-delayed fission and $$alpha$$ decay of $$^{196}$$At

Truesdale, V. L.*; Andreyev, A. N.; Ghys, L.*; Huyse, M.*; Van Duppen, P.*; Sels, S.*; Andel, B.*; Antalic, S.*; Barzakh, A.*; Capponi, L.*; et al.

Physical Review C, 94(3), p.034308_1 - 034308_11, 2016/09

 被引用回数:9 パーセンタイル:60.71(Physics, Nuclear)

A nuclear-decay spectroscopy study of the neutron-deficient isotope $$^{196}$$At is reported where an isotopically pure beam was produced using the selective Resonance Ionization Laser Ion Source and On-Line Isotope Mass Separator (CERN). The fine-structure $$alpha$$ decay of $$^{196}$$At allowed the low-energy excited states in the daughter nucleus $$^{192}$$Bi to be investigated. A $$beta$$-delayed fission study of $$^{196}$$At was also performed. A mixture of symmetric and asymmetric fission-fragment mass distributions of the daughter isotope $$^{196}$$Po (populated by $$beta$$ decay of $$^{196}$$At) was deduced based on the measured fission-fragment energies. A $$beta$$DF probability $$P_{rm beta DF}$$($$^{196}$$At) = 9(1)$$times$$10$$^{-5}$$ was determined.

論文

$$alpha$$-decay study of $$^{182,184}$$Tl

Van Beveren, C.*; Andreyev, A. N.; Barzakh, A. E.*; Cocolios, T. E.*; de Groote, R. P.*; Fedorov, D.*; Fedosseev, V. N.*; Ferrer, R.*; Ghys, L.*; Huyse, M.*; et al.

Journal of Physics G; Nuclear and Particle Physics, 43(2), p.025102_1 - 025102_22, 2016/02

 被引用回数:11 パーセンタイル:63.46(Physics, Nuclear)

$$alpha$$-decay spectroscopy of $$^{182,184}$$Tl has been performed at the CERN isotope separator on-line (ISOLDE) facility. New fine-structure $$alpha$$ decays have been observed for both isotopes. $$alpha$$-decay branching ratios of 0.089(19)$$%$$, 0.047(6)$$%$$ and 1.22(30)$$%$$ have been deduced for the (10$$^{-}$$), (7$$^{+}$$) and (2$$^{-}$$) states respectively in $$^{184}$$Tl and a lower limit of 0.49$$%$$ for the $$alpha$$-decay branching ratio of $$^{182}$$Tl. A new half-life of 9.5(2) s for the (2$$^{-}$$) state in $$^{184}$$Tl and 1.9(1) s for the low-spin state in $$^{182}$$Tl has been deduced. Using $$alpha$$-$$gamma$$ coincidence analysis, multiple $$gamma$$ rays were observed de-exciting levels in $$^{178,180}$$Au fed by $$^{182,184}$$Tl $$alpha$$ decays. The $$gamma$$ transitions connecting these low-lying states in $$^{178,180}$$Au are essential to sort the data and possibly identify bands from inbeam studies in these isotopes. Owing to the complex fine-structure $$alpha$$ decays and limited knowledge about the structure of the daughter nuclei, only partial level schemes could be constructed for both gold isotopes in the present work. Reduced $$alpha$$-decay widths have been calculated and are compared with values obtained in neighboring odd-A and even-A thallium isotopes. Except for the allowed $$alpha$$ decay of the $$^{184}$$Tl (10$$^{-}$$) state, the other fine-structure $$alpha$$ decays observed in this study are hindered. This points to strong structural changes between parent thallium and daughter gold isotopes.

論文

Shapes of $$^{192,190}$$Pb ground states from $$beta$$-decay studies using the total-absorption technique

Est$'e$vez Aguado, M. E.*; Algora, A.*; Agramunt, J.*; Rubio, B.*; Tain, J. L.*; Jord$'a$n, D.*; Fraile, L. M.*; Gelletly, W.*; Frank, A.*; Csatl$'o$s, M.*; et al.

Physical Review C, 92(4), p.044321_1 - 044321_8, 2015/10

 被引用回数:15 パーセンタイル:71.89(Physics, Nuclear)

The $$beta$$ decay of $$^{192,190}$$Pb has been studied using the total absorption technique at the ISOLDE (CERN) facility. The $$beta$$-decay strength deduced from the measurements, combined with QRPA theoretical calculations, allow us to infer that the ground states of the $$^{192,190}$$Pb isotopes are spherical. These results represent the first application of the shape determination method using the total absorption technique for heavy nuclei and in a region where there is considerable interest in nuclear shapes and shape effects.

論文

Internal decay of the (10$$^{-}$$) intruder state in $$^{184}$$Tl

Van Beveren, C.*; Andreyev, A. N.; Barzakh, A.*; Cocolios, T. E.*; Fedorov, D.*; Fedosseev, V. N.*; Ferrer, R.*; Huyse, M.*; K$"o$ster, U.*; Lane, J. F. W.*; et al.

Physical Review C, 92(1), p.014325_1 - 014325_8, 2015/07

 被引用回数:9 パーセンタイル:55.21(Physics, Nuclear)

Decay spectroscopy of $$^{184}$$Tl has been performed at the CERN Isotope Separator On-Line (ISOLDE) facility. An excitation energy of 506.1(1) keV and a half-life of 47.1(7) ms of the intruder based (10$$^{-}$$) state have been extracted. The internal decay characteristics of this state are determined and discussed, extending the systematics of such states in the even-mass thallium nuclei below neutron midshell at N = 104. The retardation factors of the isomeric M2 and E3 transitions are deduced and compared with retardation factors in neighboring odd-mass and even-mass thallium isotopes. The new information is combined with a review of hindered and unhindered $$alpha$$-decay data of $$^{187-192}$$Bi populating levels in daughter nuclei $$^{183-188}$$Tl and supports the interpretation of the intruder character of the (10$$^{-}$$) state in $$^{184}$$Tl.

論文

In-source laser spectroscopy with the laser ion source and trap; First direct study of the ground-state properties of $$^{217,219}$$Po

Fink, D. A.*; Cocolios, T. E.*; Andreyev, A. N.; Antalic, S.*; Barzakh, A. E.*; Bastin, B.*; Fedorov, D. V.*; Fedosseev, V. N.*; Flanagan, K. T.*; Ghys, L.*; et al.

Physical Review X, 5(1), p.011018_1 - 011018_15, 2015/01

 被引用回数:23 パーセンタイル:78.12(Physics, Multidisciplinary)

A Laser Ion Source and Trap (LIST) for a thick-target, isotope-separation on-line facility has been implemented at CERN ISOLDE for the production of pure, laser-ionized, radioactive ion beams. The first physics application of the LIST enables the suppression of francium contamination in ion beams of neutron-rich polonium isotopes at ISOLDE by more than 1000 with a reduction in laser-ionization efficiency of only 20. Resonance ionization spectroscopy is performed directly inside the LIST device, allowing the study of the hyperfine structure and isotope shift of $$^{217}$$Po for the first time. Nuclear decay spectroscopy of $$^{219}$$Po is performed for the first time, revealing its half-life, $$alpha$$-to-$$beta$$-decay branching ratio, and $$alpha$$-particle energy. This experiment demonstrates the applicability of the LIST at radioactive ion-beam facilities for the production and study of pure beams of exotic isotopes.

論文

$$beta$$-delayed fission of $$^{180}$$Tl

Elseviers, J.*; Andreyev, A. N.*; Huyse, M.*; Van Duppen, P.*; Antalic, S.*; Barzakh, A.*; Bree, N.*; Cocolios, T. E.*; Comas, V. F.*; Diriken, J.*; et al.

Physical Review C, 88(4), p.044321_1 - 044321_13, 2013/10

 被引用回数:38 パーセンタイル:89(Physics, Nuclear)

The detailed analysis of the $$beta$$-delayed fission data of $$^{180}$$Tl is presented. The experiment was performed by producing a pure beam of $$^{180}$$Tl by means of highly selective resonance laser ionization followed by mass separation with the ISOLDE isotope separator. A surprising asymmetric mass distribution of fission fragments from $$^{180}$$Hg, the daughter of $$^{180}$$Tl $$beta$$ decays, was obtained. Here, the energy calibration of the silicon detectors, which is crucial for a proper determination of the fission fragments' energy and mass split, is presented and the total kinetic energy and its dependence on the mass split ratio is discussed. A more precise $$beta$$-delayed fission probability of 3.2(2)$$times$$10$$^{-3}$$$$%$$ was deduced.

論文

Measurement of the first ionization potential of astatine by laser ionization spectroscopy

Rothe, S.*; Andreyev, A. N.*; Antalic, S.*; Borschevsky, A.*; Capponi, L.*; Cocolios, T. E.*; De Witte, H.*; Eliav, E.*; Fedorov, D. V.*; Fedosseev, V. N.*; et al.

Nature Communications (Internet), 4, p.1835_1 - 1835_6, 2013/05

 被引用回数:79 パーセンタイル:94.43(Multidisciplinary Sciences)

The radioactive element astatine exists only in trace amounts in nature. Its properties can therefore only be explored by study of smallest quantities of artificially produced isotopes or by performing theoretical calculations. One of the most important properties influencing the chemical behaviour is the energy required to remove one electron from the valence shell, referred to as the ionization potential (IP). Here we use laser spectroscopy to probe the optical spectrum of astatine near the ionization threshold. The observed series of Rydberg states allowed the deduction of the IP of the astatine atom for the first time. New ab initio calculations were performed to support the experimental result. The measured value of IP(At) serves as a benchmark for quantum chemistry calculations of the properties of astatine as well as for the theoretical prediction of the ionization potential of super-heavy element 117, the heaviest homologue of astatine.

論文

$$alpha$$-decay spectroscopy of the chain $$^{179}$$Tl$$^{g}$$ $$rightarrow$$ $$^{175}$$Au$$^{g}$$ $$rightarrow$$ $$^{171}$$Ir$$^{g}$$ $$rightarrow$$ $$^{167}$$Re$$^{m}$$

Andreyev, A. N.*; Liberati, V.*; Antalic, S.*; Ackermann, D.*; Barzakh, A.*; Bree, N.*; Cocolios, T. E.*; Diriken, J.*; Elseviers, J.*; Fedorov, D.*; et al.

Physical Review C, 87(5), p.054311_1 - 054311_8, 2013/05

 被引用回数:15 パーセンタイル:70.34(Physics, Nuclear)

$$alpha$$-decay studies of $$^{179}$$Tl$$^{g}$$ and its dahghter products $$^{175}$$Au$$^{g}$$ and $$^{171}$$Ir$$^{g}$$ were carried out in two complementary experiments at the mass separator ISOLDE (CERN) and velocity filter SHIP (GSI). The nucluesu $$^{175}$$Au$$^{g}$$ has $$alpha$$ decay properties of half-life 207 ms and $$alpha$$-decay energy 6433 keV. The ground state spins and parities for $$^{175}$$Au and $$^{171}$$Ir were determined to be 1/2$$^{+}$$.

論文

High-capacity electrode material BC$$_{3}$$ for lithium batteries proposed by ${it ab initio}$ simulations

Kuzubov, A. A.*; Fedorov, A. S.*; Eliseeva, N. S.*; Tomilin, F. N.*; Avramov, P.; Fedorov, D. G.*

Physical Review B, 85(19), p.195415_1 - 195415_4, 2012/05

 被引用回数:38 パーセンタイル:81.91(Materials Science, Multidisciplinary)

The absorption energy and diffusion rates of lithium atoms inside graphitelike boron carbide (BC$$_{3}$$) crystal are investigated by the ${it ab initio}$ pseudopotential density-functional method using generalized gradient approximation. It is shown that lithium may effectively intercalate this structure with the maximum lithium concentration corresponding to Li$$_{2}$$BC$$_{3}$$ stoichiometry, which is threefold in comparison to lithium in graphite. The potential barrier values for lithium diffusion both at low and maximum concentration are about 0.19 eV, so lithium atoms inside the BC$$_{3}$$ structure can move easily. These findings suggest that boron carbide looks like a good candidate as an anode material in lithium ion batteries.

論文

Relative isomer abundance of fullerenes and carbon nanotubes correlates with kinetic stability

Fedorov, A. S.*; Fedorov, D. A.*; Kuzubov, A. A.*; Avramov, P.; 西村 好史*; Irle, S.*; Witek, H. A.*

Physical Review Letters, 107(17), p.175506_1 - 175506_5, 2011/10

 被引用回数:21 パーセンタイル:72.38(Physics, Multidisciplinary)

A methodology to evaluate the kinetic stability of carbon nanostructures is presented based on the assumption of the independent and random nature of thermal vibrations. The kinetic stability is directly correlated to the cleavage probability for the weakest bond of a given nanostructure. The application of the presented method to fullerenes and carbon nanotubes yields clear correlation to their experimentally observed relative isomer abundances. The general and simple formulation of the method ensures its applicability to other nanostructures for which formation is controlled by kinetic factors.

論文

New type of asymmetric fission in proton-rich nuclei

Andreyev, A. N.*; Elseviers, J.*; Huyse, M.*; Van Duppen, P.*; Antalic, S.*; Barzakh, A.*; Bree, N.*; Cocolios, T. E.*; Comas, V. F.*; Diriken, J.*; et al.

Physical Review Letters, 105(25), p.252502_1 - 252502_5, 2010/12

 被引用回数:181 パーセンタイル:97.19(Physics, Multidisciplinary)

A very exotic process of $$beta$$-delayed fission of $$^{180}$$Tl is studied in detail by using resonant laser ionization with subsequent mass separation at ISOLDE (CERN). In contrast to common expectations, the fission-fragment mass distribution of the post-$$beta$$-decay daughter nucleus $$^{180}$$Hg ($$N$$/$$Z$$ = 1.25) is asymmetric. This asymmetry is more surprising since a mass-symmetric split of this extremely neutron-deficient nucleus would lead to two $$^{90}$$Zr fragments, with magic $$N$$ = 50 and semi-magic $$Z$$ = 40. This is a new type of asymmetric fission, not caused by large shell effects related to fragment magic proton and neutron numbers, as observed in the actinide region. The newly-measured branching ratio for $$beta$$-delayed fission of $$^{180}$$Tl is 3.6(7)$$times$$10$$^{-3}$$ %.

論文

Atomic and electronic structure of new hollow-based symmetric families of silicon nanoclusters

Avramov, P.; Fedorov, D. G.*; Sorokin, P. B.*; Chernozatonskii, L. A.*; Gordon, M. S.*

Journal of Physical Chemistry C, 111(51), p.18824 - 18830, 2007/12

 被引用回数:12 パーセンタイル:40(Chemistry, Physical)

内部に任意の大きなフラーレン型の空間を持つ安定なSiナノクラスターファミリーを系統的に構築した。さらに、5員環,6員環接合を介してこれらのナノクラスターを結合することによって複合構造をデザインした。提案した物質の原子配置と電子構造を半経験的量子力学的手法を用いて計算した。それぞれのファミリー内でバンドギャップと安定性はクラスターの実効的な大きさに反比例することが明らかになった。クラスターは、親となるシリコンフラーレンから受け継いだ非常にバラエティに富む構造と対称性を持つ。複合体は、接合に関係する特異な電子構造を持った擬分子のように電子を閉じ込める。量子ドットとその複合体はその内部空間にゲスト原子を内包しうる。それゆえ、電子特性を制御可能で有望な新規ナノ材料を提供しうる。

論文

Density-functional theory study of the electronic structure of thin Si/SiO$$_{2}$$ quantum nanodots and nanowires

Avramov, P.; Kuzubov, A. A.*; Fedorov, A. S.*; Sorokin, P. B.*; Tomilin, F. N.*; 前田 佳均

Physical Review B, 75(20), p.205427_1 - 205427_8, 2007/05

 被引用回数:18 パーセンタイル:60.76(Materials Science, Multidisciplinary)

本研究では、狭い界面を持つ5角形のSi/SiO$$_{2}$$量子ナノドット(QDs,直径1.6nm)及びナノワイヤ(NWs)を提案し、元となるシリコンの準安定構造(直径1.2nm)とともに、その原子構造と電子構造を、クラスター近似B3LYP/6-31G$$^{*}$$及び周期的境界条件(PBC)平面波近似(PW)擬ポテンシャル(PP)局所密度近似法を用いて計算した。最も小さい擬球状QD(Si$$_{85}$$)の全状態密度(TDOS)はPBC PW PP LDAで計算した結晶性シリコンのTDOSによく一致した。伸長したSiQDsとSiNWsは金属的特性を持った電子構造を示す。しかし、表面に酸化層を持つとSi/SiO$$_{2}$$クラスターのTDOS中にバンドギャップができる。これらの粒子の価電子帯の上端と伝導帯の底は、核となるSiに由来した電子状態によって形成される。理論的に予測されるバンドギャップの幅は、Si/SiO$$_{2}$$クラスターの長さによって決定され、さらに、シリカに埋め込まれたナノシリコンのフォトルミネッセンススペクトルにおけるサイズ効果を高い精度で説明できる。

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