bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electron tunneling through single self‐assembled InAs quantum dots coupled to nanogap electrodes
Authors: Shibata K. , Jung M. , Buizert C. , Oiwa A. , Hirakawa K. , Machida T. , Tarucha S. 
Published: May 2008

AbstractWe have investigated electronic properties of self‐assembled InAs quantum dots (QDs) grown on GaAs surfaces by using metallic Au and Al leads with narrow gaps. The fabricated junctions with Au nanogap electrodes show single electron tunneling behaviors. When coupling between electrons in the QDs and the electrodes is strong, Kondo effect with relatively high Kondo temperature TK of 10‐15 K is observed. The samples with superconducting (SC) Al electrodes also exhibit clear Coulomb blockade effects. Furthermore, clear suppression in conductance is observed around VSD = 0 V for a voltage range of 4Δ /e at T = 40 mK, where Δ is the SC energy gap of Al, demonstrating successful fabrication of the SC‐QD‐SC junction in the self‐assembled InAs QD system. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tunneling mechanism of GaAs ultrashallow sidewall tunnel junction
Authors: Ohno Takeo , Oyama Yutaka , Sato Shota , Nishizawa Jun‐ichi 
Published: May 2008

AbstractConductance‐voltage (G ‐V) and current‐voltage (J ‐V) measurements were applied to reveal the tunneling mechanisms of GaAs ultra‐shallow sidewall tunnel junctions, which were fabricated by molecular layer epitaxy. From the G ‐V results, peaks were detected at 2, 12 and 14 THz at 6 K. In the J ‐V measurements, the fine structure near the peak voltage and a step in the tunneling current in the negative resistance region can also be observed. The tunneling mechanism is discussed in terms of the band transition, deep level and phonon‐assisted tunneling. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Improved EL characteristics of polyfluorene/PBD‐mixed layer by wet process
Authors: Yamaguchi H. , Komoriya M. , Kamata N. 
Published: May 2008

AbstractWe fabricated poly(9,9‐di‐n ‐octylfluorenyl‐2,7‐dilyl) (PFO) EL devices with PBD as an electron transport material. The PBD/PFO double‐layer, which was spin‐coated sequentially by choosing solvents, and the mixed layer devices were fabricated successfully. Factors of improvement in EL intensity were eight and five for mixed layer (PBD:PFO=7:3) and double layer devices, respectively, when compared with that of the PFO single layer device. The combination of mixed layer device with PMPS:PBD:PFO= 60:35:5 showed further improvement in EL intensity by a factor of 2.5 from the mixed layer device without PMPS. These results are promising for optimizing polymer EL devices based on the wet process. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Temperature‐dependent high‐frequency performance of deep submicron AlGaN/GaN HEMTs
Authors: Cuerdo R. , Pei Y. , Recht F. , Fichtenbaum N. , Keller S. , Denbaars S. P. , Calle F. , Mishra U. K. 
Published: May 2008

AbstractA study of the low temperature DC and RF performance of deep submicron AlGaN/GaN high electron mobility transistors (HEMTs) is reported. From 300 K to 100 K both extrinsic transconductance and drain current increase by ∼30%, mainly due to the lowering of the optical phonon scattering that allows higher electron mobility. Source and drain resistances improve too, which contributes to the 15‐20% increase of ftand fmax. The low temperature small signal model has also been extracted accurately at every 50 K. Inductances and capacitances remain constant in the range of temperatures measured. The intrinsic transconductance can be also considered temperature independent, but the output conductance decreases from 300 K to 100 K indicating a better confinement of the 2DEG. The HEMT performance obtained at 100 K can be reached at room temperature by reducing the parasitic resistances and improving the GaN buffer isolation. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Improved initial epitaxial growth of β‐FeSi2 on Si(111) substrate by Al‐doping
Authors: Hashimoto Syoutaro , Terai Yoshikazu , Fujiwara Yasufumi 
Published: May 2008

AbstractEffects of Al‐doping on the iron silicide growth were investigated in reactive deposition epitaxy (RDE) on Si(111) substrates. ε‐FeSi(111) layer was grown on the Si(111) substrate when the Fe of 50 Å was deposited at 750 °C. In Al‐doped samples grown by co‐deposition of Fe and Al, both the crystal orientation of ε‐FeSi(111)//Si(111) and the surface flatness of the layer were improved with increasing Kundsen‐cell temperature of Al (TAl). The highly‐oriented ε‐FeSi templates were annealed at 850 °C for a phase transition from ε‐FeSi to β‐FeSi2. X‐ray diffraction (XRD) measurements of the annealed samples showed that the crystal orientation of β‐FeSi2(202)(220)//Si(111) strongly depended on that of the ε‐FeSi//Si. In undoped samples, XRD peaks originating from polycrystalline β‐FeSi2 were observed in 2θ scan measurements. On the other hand, the peak intensities from the β‐FeSi2 polycrystal became much small in the Al‐doped β‐FeSi2 grown at TAl = 925 °C. These results revealed that Al‐doping during the RDE growth promotes the epitaxial growth of ε‐FeSi(111)//Si(111) and the crystallographic orientation relationship between ε‐FeSi and Si affects the epitaxial growth of β‐FeSi2(101)(110) on Si(111) by the post‐annealing. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Laser‐induced formation of nonradiative centers observed by two‐wavelength excited photoluminescence
Authors: Ogawa H. , Uchiyama N. , Kamata N. , Arakawa Y. 
Published: May 2008

AbstractBy observing an intensity change of photoluminescence (PL) due to the addition of a below‐gap excitation light (BGE effect), a quantitative determination of nonradiative recombination (NRR) centers becomes possible. We observed an irreversible decrease of the BGE effect, together with a distinct PL quenching, when a GaN/AlGaN quantum well was irradiated by a Nd:YAG laser (1.17 eV) in addition to a D2 lamp (4.88 eV). The decrease is considered to be due to the formation of a NRR center at sample surface. An equivalent rate equation analysis explained both of the experimental change rather well. The observation of a defect formation enables us to understand the nature of NRR centers more dynamically, thus it is effective for determining the origin of the defect and optimizing the growth condition in nitride‐based materials. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electro‐optic property of ZnO:Mn epitaxial films
Authors: Oshio T. , Masuko K. , Ashida A. , Yoshimura T. , Fujimura N. 
Published: May 2008

AbstractMn doping effect on the dielectric and electro‐optic (E‐O) property of ZnO epitaxial films was studied. The leakage current of the ZnO film is drastically decreased by doping Mn with the concentration of 3‐5 at%. Although, ZnO: 4 at% Mn with the lowest leakage current has the largest frequency dispersion of birefringence shift (Δ n) at 1 kHz, and its E‐O coefficient (rc) was larger than that of ZnO single crystal. It is presumably caused by another polarization effect but spontaneous polarization, such as space charge. To investigate the origin of the dispersion of Δ n, discharging property was evaluated. When the signal at 1 kHz was applied, ZnO: 3 and 5 at% Mn showed the discharging with relaxation time of 5 msec. Furthermore, the discharging property with same relaxation time was observed at 20 kHz at where the dispersion of Δ n was not observed. However, ZnO: 4 at% Mn does not show such a discharging behavior. Therefore, it is considered that the space charge is not the origin of the dispersion of Δ n. On the other hand, the dispersion of Δ n was minimum and no dielectric dispersion was observed at 20 kHz for all samples. The rc of ZnO: 3, 4 and 5 at% Mn measured at 20 kHz, which should be the rc originated from the spontaneous dipolar polarization, were derived to be 0.81, 0.81 and 0.62 pm/V, respectively. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Trap states in n‐GaN grown on AlN/sapphire template by MOVPE
Authors: Ito T. , Yoshikawa M. , Watanabe A. , Egawa T. 
Published: May 2008

AbstractUsing epitaxial AlN/sapphire templates, high crystalline quality GaN films are grown on them by metal organic chemical vapour deposition. The electron traps behaviour of these GaN films were observed by deep level transient spectroscopy (DLTS). Four distinct trap levels were ob‐served in both n‐GaN grown on AlN/sapphire template and on conventional low temperature buffer layer (LT‐BL)/sapphire. The magnitude the of the DLTS signal E1 and E2 were almost same. It suggests that E1 is not only associate with dislocation density but also other defect. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fabrication of blue‐shifted Fabry‐Perot laser diodes for integration with optical passive waveguides
Authors: Byun Young Tae , Kim Suhyun , Kim Sun Ho , Chung Youngchul 
Published: May 2008

AbstractLaser diodes monolithically integrated with a passive waveguide is fabricated by using a quantum‐well intermixing. This technique first consists of using a photolithography and reactive ion etching process to create a Si3N4 implant mask region on the sample. This is followed by a 1‐MeV phosphorous ion implantation at a dose of 5×1014 P+ ions/cm2 at 200 °C. A subsequent two‐step RTA annealing induces QW intermixing through the diffusion of the point defects. For the integration of a laser diode and a passive waveguide, the mirror facet is formed by creating a deeply‐etched trench between an active and passive region by RIE etching. The lasing operation and shifted lasing wavelengths are measured and compared experimentally. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Energy dependent carrier relaxation in self‐assembled InAs/GaAs quantum dots
Authors: Ling H. S. , Lee C. P. , Wang S. Y. , Lo M. C. 
Published: May 2008

AbstractWe performed the selective excitation photoluminescence (SEPL) spectroscopy studies on InAs/GaAs self‐assembled quantum dots (QDs). Under different excitation energies, different groups of QDs are selected and emit light. The excited carriers relax to the ground state through different mechanisms when excited at different energies. Three distinct regions with different mechanisms in carrier excitation and relaxation are identified in the emission spectra. These three regions can be categorized, from high energy to low energy, as continuum absorption, electronic state excitation, and multi‐phonon resonance. The QDs' special joint density‐of‐state tail extending from the wetting layer peak facilitates the carrier relaxation and was suggested to explain these spectral results. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
GaAs area‐selective regrowth with molecular layer epitaxy for integration of low noise and power transistors, and Schottky diodes
Authors: Nishizawa J. , Płotka P. , Kurabayashi T. 
Published: May 2008

AbstractWe have developed a GaAs mm‐wave power static induction transistor (SIT) with a regrown source‐drain offset. It was fabricated with low‐temperature, area‐selective molecular layer epitaxial regrowth in a process compatible with that of a low‐noise high‐frequency ideal static induction transistor. The fmax of the power SIT was 111 GHz at gm of 220 mS/mm. These values can be improved with gate engineering. Our method can be used for fabrication of mm‐wave system‐on‐chip wafers including also Schottky barrier diodes. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth and characterization of GaSb heteroepitaxial layers on Si(111) substrates
Authors: Toyota H. , Yasuda T. , Endoh T. , Jinbo Y. , Uchitomi N. 
Published: May 2008

AbstractWe investigated the growth of GaSb layers and GaSb/‐AlGaSb multiple quantum well (MQW) structures using an AlSb initiation layer on Si(111) substrates. The entire growth was monitored using reflection high‐energy electron diffraction (RHEED). The GaSb epitaxial films and MQWstructures were characterized by X‐ray diffraction (HRXRD), atomic force microscopy (AFM) and photoluminescence (PL) spectroscopy.Our results suggest that high‐quality (111)‐oriented GaSb films with a mirror surface can be obtained using the present growth condition. The PL peak energy of the MQWs on Si(111) substrates is almost temperature independent up to ∼120 K and exhibits relatively smaller variation with temperature compared to that of the MQWs grown on Si(001) substrates. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Study of energetics of end‐on and side‐on peroxide coordination in ligated Cu2O2 models with State‐Specific Equation of Motion Coupled Cluster Method
Authors: Kong Liguo , Nooijen Marcel 
Published: May 2008

AbstractNewly developed State‐Specific Equation of Motion Coupled Cluster method (SS‐EOMCC) is used to study the relative energetics of μ‐1:2(trans end‐on) and μ‐η2:η2(side‐on) peroxo isomers of Cu2O2 fragments with 0 and 2 ammonia ligands. These model systems had been shown to be problematic to multireference perturbation theory (MRPT) and density functional theory (DFT) methods. In spite of the small reference space used, SS‐EOMCC gives much improved results by comparison to benchmark CR‐CC results. In addition to the fully symmetric 1Ag state, 1Bg and 3Bg states are also computed, demonstrating the complexity of the systems under study, as seen from the energy crossing at intermediate geometries. Spin‐flip idea is natural in our current theoretical framework and is tried for the model systems. It is argued that an important feature of the SS‐EOMCC method is that orbitals are optimized in the presence of dynamical correlation. This is the prime reason that a very small set of active orbitals can be used to achieve satisfactory results. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Real options and real value: the role of employee incentives to make specific knowledge investments
Authors: Wang Heli , Lim Sonya Seongyeon 
Published: May 2008

AbstractReal options reasoning emphasizes the strategic value of making flexible investments in a turbulent environment. Employees' investments in specific human capital are often critical to the success of a real option project, but the very flexibility that allows a firm to change course in response to new information also affects employees' incentives to make such specific human capital investments. We develop a model of real option investment that explicitly incorporates the role of employee incentives. The model suggests that the effect of investing in a real option project on employee incentives may be positive, further increasing the value of the project, or negative, sometimes more than offsetting the benefit of flexibility and resulting in reduced project value. Therefore, firms and managers should take into consideration the role of employee incentives when applying real options logic to investment decision making. Copyright © 2008 John Wiley & Sons, Ltd.
7‐Nitroindazole, nitric oxide synthase inhibitor, attenuates physical dependence on butorphanol in rat
Authors: Tian Yu‐Hua , Lee Kwang‐Wook , You In‐Jee , Lee Seok‐Yong , Jang Choon‐Gon 
Published: May 2008

AbstractButorphanol is a synthetic opioid agonist/antagonist analgesic agent that mainly exerts its effects through κ‐opioid receptors. It has been demonstrated that κ‐opioid receptors preferentially mediate the development of physical dependence upon butorphanol and the associated withdrawal syndrome. However, it is not fully understood whether or not nNOS‐containing neurons in the various brain regions play an important role in butorphanol withdrawal. Therefore, this study was conducted to determine whether the selective nNOS inhibitor, 7‐NI, modifies the development of butorphanol withdrawal and changes of nNOS expressions in different brain regions in physically butorphanol‐dependent rats. The first part of the study focused on withdrawal behaviors in male Sprague‐Dawley rats. Physical dependence was induced by a 72‐h i.c.v. infusion with butorphanol (26 nmol/μl/h) and withdrawal was subsequently precipitated by i.c.v. challenge with naloxone (48 nmol/5 μl/rat) 2 h after termination of the butorphanol infusion. The butorphanol/7‐NI coadministration group showed a significant decrease in several signs of withdrawal such as teeth chattering, as compared with the butorphanol‐treated group. In the second part of the study, immunohistochemical analysis was performed to determine the expression of nNOS in the various brain regions. In the butorphanol/7‐NI coadministration group, the number of cells labeled for nNOS was significantly lower in the various brain regions (including the caudate putamen, nucleus accumbens, and hippocampus) than in the butorphanol group. Therefore, 7‐NI decreased in butorphanol‐induced physical dependence and nNOS expression. Taken together, these findings suggest that the nNOS system is involved in the development of butorphanol‐induced physical dependence, and 7‐NI has potential clinical application as a candidate for the treatment of opioid withdrawal syndrome. Synapse 62:582–589, 2008. © 2008 Wiley‐Liss, Inc.
Azidokomplexe von Vanadium(IV) und Vanadium(V): (Ph4P)2[VOCl2(μ‐N3)]2 und (Ph4P)2[VOCl(μ‐N3)(N3)2]2
Authors: Burghaus Olaf , Neumüller Bernhard , Dehnicke Kurt 
Published: May 2008

AbstractAzido Complexes of Vanadium(IV) and Vanadium(V): (Ph4P)2[VOCl2(μ‐N3)]2 and (Ph4P)2[VOCl(μ‐N3)(N3)2]2(Ph4P)2[VOCl2(μ‐N3)]2 (1) was prepared by reaction of (Ph4P)[VO2Cl2] with trimethylsilylazide in the molar ratio 1:2 in dichloromethane solution to give dark green, moisture sensitive, non‐explosive single crystals. The reaction is accompanied by the formation of the dark blue side‐product (Ph4P)2[VOCl(μ‐N3)(N3)2]2 (2a), which can be obtained as the main product by application of a large excess of Me3SiN3. Dark blue needles of 2a crystallize spontaneously from the CH2Cl2 solution within one hour at 4 °C. After standing at 4 °C under its mother liquid within 24 hours a first‐order phase transition of 2a occurs forming dark blue prismatic single crystals of 2b. According to single crystal X‐ray structure determinations, 2a and 2b crystallize in the same type of space group $\rm P{\bar 1}$, however, with different lattice dimensions.The vanadium(IV) complex 1 is characterized by X‐ray structure determination and by vibrational spectroscopy (IR, Raman) as well as by EPR spectroscopy, whereas 2b is characterized by IR spectroscopy.1: Space group P21/n, Z = 2, a = 1009.5(1), b = 1226.6(2), c = 1943.0(2) pm, β = 98.42(1)°, R1 = 0.0672. The complex anion $\rm [VOCl_{2}(\mu-N_{3})]^{2-}_{{2}/{2}}$ forms centrosymmetric units with V2N2‐four‐membered rings with a V···V distance of 335.6(1) pm and coordination number five on the vanadium(IV) atoms.2a: Space group $\rm P{\bar 1}$, Z = 1, a = 1089.0(2), b = 1097.1(2), c = 1310.1(2) pm, α = 92.99(1)°, β = 106.12(2)°, γ = 117.05(2)°, V = 1309.8(4) Å3, dcalc. = 1.440 g·cm−3, R1 = 0.0384. The complex anion forms centrosymmetric units of symmetry Ci with V2N2 four‐membered rings and VN bond lengths of 200.4(3) and 234.4(2) pm, respectively. The non‐bonding V···V distance amounts to 356.2(1) pm.2b: Space group $\rm P{\bar 1}$, Z = 1, a = 1037.3(2), b = 1157.6(2), c = 1177.2(2) pm, α = 98.48(2)°, ° = 103.82(2)°, γ = 106.33(2)°, V = 1281.8(4) Å3, dcalc. = 1.471 g·cm−3, R1 = 0.0724. The structure of the complex anion $\rm [VOCl(\mu-N_{3})(N_{3})_{2}]^{2-}_{{2}/{2}}$ is similar to the anion of 2a with VN bond lengths of the four‐membered V2N2 ring of 203.3(4) and 235.2(4) pm, respectively, and a non‐bonding V···V distance of 357.5(1) pm.
Building the “Phosphoindigo” Backbone by Oxidative Coupling of Phosphindolin‐3‐ones with Selenium Dioxide
Authors: Vollbrecht Sebastian , Dobreva Guergana , Cartis Ioana , du Mont Wolf‐W. , Jeske Jörg , Ruthe Frank , Jones Peter G. , Ernst Ludger , Grahn Walter , Papke Ulrich , Marzini Michael , Mayer Hermann A. 
Published: May 2008

AbstractOxidative coupling of racemic 1‐ethoxy‐1‐oxophosphindolin‐3‐one (1) and its 5‐CF3‐derivative 6 with SeO2 furnishes 1,1′‐diphosphaindigo derivatives 5 and 7 as bis‐phosphinic esters, i. e. as PV‐compounds. Like indigo and thioindigo, 5 and 7 exist in the E‐configuration; the crude products of 5 and 7 are mixtures of isomers that are trans‐ and cis‐configurated with respect to the relative orientation of the ester groups oat phosphorus. The structure of the centrosymmetric E‐P(R)P′(S) isomer [(E)‐trans‐isomer] of 5 was determined by X‐ray crystallography. Ester cleavage of 5, followed by addition of triethylamine to bis‐phosphinic acid 9 (the 1,1,1′,1′‐tetroxide of “phosphoindigo”), furnishes the related bis‐triethylammonium salt 10 as a crystalline hydrate that exhibits an extended hydrogen bonding network.
Addition von kationischen Lewis‐Säuren [M′Ln]+ (M′Ln = Fe(CO)2Cp, Fe(CO)(PPh3)Cp, Ru(PPh3)2Cp, Re(CO)5, ${1 \over 2}$ Pt(PPh3)2, W(CO)3Cp an die anionischen Thiocarbonyl‐Komplexe [HB(pz)3(OC)2M(CS)]− (M = Mo, W; pz = 3,5‐dimethylpyrazol‐1‐yl)
Authors: Knauer Wolfgang , Beck Wolfgang 
Published: May 2008

AbstractAddition of Cationic Lewis Acids [M′Ln]+ (M′Ln = Fe(CO)2Cp, Fe(CO)(PPh3)Cp, Ru(PPh3)2Cp, Re(CO)5, ${1 \over 2}$ Pt(PPh3)2, W(CO)3Cp to the Anionic Thiocarbonyl Complexes [HB(pz)3(OC)2M(CS)]− (M = Mo, W; pz = 3,5‐dimethylpyrazol‐1‐yl)Adducts from Organometallic Lewis Acids [Fe(CO)2Cp]+, [Fe(CO)(PPh3)Cp]+, [Ru(PPh3)2Cp]+, [Re(CO)5]+, [${1 \over 2}$ Pt(PPh3)2]+, [W(CO)3Cp]+ and the anionic thiocarbonyl complexes [HB(pz)3(OC)2M(CS)]− (M = Mo, W) have been prepared. Their spectroscopic data indicate that the addition of the cations occurs at the sulphur atom to give end‐to‐end thiocarbonyl bridged complexes [HB(pz)3(OC)2MCSM′Ln].
Magnetic, Optical, and Electronic Properties of the Phosphide Oxides REZnPO (RE = Y, La–Nd, Sm, Gd, Dy, Ho)
Authors: Lincke Hannes , Glaum Robert , Dittrich Volker , Tegel Marcus , Johrendt Dirk , Hermes Wilfried , Möller Manfred H. , Nilges Tom , Pöttgen Rainer 
Published: May 2008

AbstractWell‐shaped yellow to red transparent single crystals of the phosphide oxides REZnPO (RE = Y, La–Nd, Sm, Gd, Dy, Ho) were synthesized from the elements and ZnO in NaCl/KCl fluxes in sealed silica ampoules. Four structures (NdZnPO type, R3m) were refined from single crystal X‐ray diffractometer data: a = 388.5(2), c = 3032(1) pm, wR2 = 0.0380, 360 F2 values for YZnPO, a = 394.6(2), c = 3071(1) pm, wR2 = 0.0587, 226 F2 values for SmZnPO, a = 392.2(2), c = 3056(1) pm, wR2 = 0.0262, 462 F2 values for GdZnPO, and a = 389.33(6), c = 3030.5(4) pm, wR2 = 0.0453, 217 F2 values for DyZnPO each with 14 variables per refinement. The structures are composed of alternate stacks of (RE3+O2−) and (Zn2+P3−) layers with covalent RE–O and ZñP bonding within and weak ionic bonding between the layers. The zinc and oxygen atoms have slightly distorted tetrahedral coordination by atoms of phosphorus and the rare earth element, respectively. According to the electron precise formulation RE3+Zn2+P3−O2−, these pnictide oxides are transparent in visible light. Susceptibility measurements on β‐CeZnPO, β‐PrZnPO, and GdZnPO reveal Curie‐Weiss paramagnetism with experimental magnetic moments of 2.31, 3.60, and 7.72 μB/RE atoms, respectively. β‐CeZnPO and β‐PrZnPO show antiferromagnetic order with Néel temperatures of 7.4 (Ce) and 2.2 (Pr) K. GdZnPO shows no magnetic ordering down to 2 K. Single crystal absorption spectra measured for REZnPO (RE = Y, La, Pr, Nd, Sm, Dy) in the NIR‐Vis region reveal unexpected variations for the optical band gap of these phosphide oxides. For RE = Pr, Nd, Sm, Dy, Ho f‐f electronic transitions with nicely resolved ligand‐field splittings are observed in the range 6000–20000 cm−1. DFT band structure calculations show similarity between the valence bands of tetragonal and rhombohedral REZnPO as they possess mainly P‐3p character. In both cases, the conduction bands have mainly Zn‐4s character, but a significant contribution of RE‐5d occurs in rhombohedral REZnPO, which is responsible for a smaller optical band gap for the latter compounds. Variations of the energy gaps of tetragonal REZnPO can be explained by hybridization of Zn‐4s + RE‐5d + RE‐4f orbitals for the conduction band. DFT volume optimizations of α‐ and β‐PrZnPO show β‐PrZnPO to be more stable by 10.7 kJ mol−1.