dysprosium ← holmium → erbium - ↑ Ho ↓ Es 67Ho Periodic table
Appearance
silvery white
General properties
Name, symbol, number	holmium, Ho, 67
Pronunciation	/ˈhoʊlmiəm/ HOHL-mee-əm
Element category	lanthanide
Group, period, block	n/a, 6, f
Standard atomic weight	164.93032
Electron configuration	[Xe] 4f11 6s2
Electrons per shell	2, 8, 18, 29, 8, 2 (Image)
Physical properties
Phase	solid
Density (near r.t.)	8.79 g·cm−3
Liquid density at m.p.	8.34 g·cm−3
Melting point	1734 K, 1461 °C, 2662 °F
Boiling point	2993 K, 2720 °C, 4928 °F
Heat of fusion	17.0 kJ·mol−1
Heat of vaporization	265 kJ·mol−1
Molar heat capacity	27.15 J·mol−1·K−1
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 1432 1584 (1775) (2040) (2410) (2964)
Atomic properties
Oxidation states	3 (basic oxide)
Electronegativity	1.23 (Pauling scale)
Ionization energies	1st: 581.0 kJ·mol−1
	2nd: 1140 kJ·mol−1
	3rd: 2204 kJ·mol−1
Atomic radius	176 pm
Covalent radius	192±7 pm
Miscellanea
Crystal structure	hexagonal
Magnetic ordering	paramagnetic
Electrical resistivity	(r.t.) (poly) 814 nΩ·m
Thermal conductivity	16.2 W·m−1·K−1
Thermal expansion	(r.t.) (poly) 11.2 µm/(m·K)
Speed of sound (thin rod)	(20 °C) 2760 m·s−1
Young's modulus	64.8 GPa
Shear modulus	26.3 GPa
Bulk modulus	40.2 GPa
Poisson ratio	0.231
Vickers hardness	481 MPa
Brinell hardness	746 MPa
CAS registry number	7440-60-0
Most stable isotopes
Main article: Isotopes of holmium
iso NA half-life DM DE (MeV) DP 163Ho syn 4570 yr ε 0.003 163Dy 164Ho syn 29 min ε 0.987 164Dy 165Ho 100% 165Ho is stable with 98 neutrons 166Ho syn 26.763 h β− 1.855 166Er 167Ho syn 3.1 h β− 1.007 167Er
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Holmium ( /ˈhoʊlmiəm/ HOHL-mee-əm) is a chemical element with the symbol Ho and atomic number 67. Part of the lanthanide series, holmium is a rare earth element. Its oxide was first isolated from rare earth ores in 1878 and the element was named after the city of Stockholm.

Elemental holmium is a relatively soft and malleable silvery-white metal. It is too reactive to be found uncombined in nature, but when isolated, is relatively stable in dry air at room temperature. However, it reacts with water and rusts readily, and will also burn in air when heated.

Holmium is found in the minerals monazite and gadolinite, and is usually commercially extracted from monazite using ion exchange techniques. Its compounds in nature, and in nearly all of its laboratory chemistry, are trivalently oxidized, containing Ho(III) ions. Trivalent holmium ions have fluorescent properties similar to many other rare earth ions (while yielding their own set of unique emission light lines), and holmium ions are thus used in the same way as some other rare earths in certain laser and glass colorant applications.

Holmium has the highest magnetic strength of any element and therefore is used for the polepieces of the strongest static magnets. Because holmium strongly absorbs neutrons, it is also used in nuclear control rods.

Characteristics[link]

Physical properties[link]

Ho₂O₃, left: natural light, right: fluorescent lamp light

Holmium is a relatively soft and malleable element that is fairly corrosion-resistant and stable in dry air at standard temperature and pressure. In moist air and at higher temperatures, however, it quickly oxidizes, forming a yellowish oxide. In pure form, holmium possesses a metallic, bright silvery luster.

Holmium oxide has some fairly dramatic color changes depending on the lighting conditions. In daylight, it is a tannish yellow color. Under trichromatic light, it is a fiery orange red, almost indistinguishable from the appearance of erbium oxide under the same lighting conditions. The change is related to the sharp emission bands of the trivalent ions of these elements, acting as phosphors.^[1]

Holmium has the highest magnetic moment (10.6 µ
B) of any naturally occurring element and possesses other unusual magnetic properties. When combined with yttrium, it forms highly magnetic compounds.^[2] Holmium is paramagnetic at ambient conditions, but is ferromagnetic at temperatures below 19 K.^[3]

Chemical properties[link]

Holmium metal tarnishes slowly in air and burns readily to form holmium(III) oxide:

4 Ho + 3 O₂ → 2 Ho₂O₃

Holmium is quite electropositive and is generally trivalent. It reacts slowly with cold water and quite quickly with hot water to form holmium hydroxide:

2 Ho (s) + 6 H₂O (l) → 2 Ho(OH)₃ (aq) + 3 H₂ (g)

Holmium metal reacts with all the halogens:

2 Ho (s) + 3 F₂ (g) → 2 HoF₃ (s) [pink]

2 Ho (s) + 3 Cl₂ (g) → 2 HoCl₃ (s) [yellow]

2 Ho (s) + 3 Br₂ (g) → 2 HoBr₃ (s) [yellow]

2 Ho (s) + 3 I₂ (g) → 2 HoI₃ (s) [yellow]

Holmium dissolves readily in dilute sulfuric acid to form solutions containing the yellow Ho(III) ions, which exist as a [Ho(OH₂)₉]³⁺ complexes:^[4]

2 Ho (s) + 3 H₂SO₄ (aq) → 2 Ho³⁺ (aq) + 3 SO2−
4 (aq) + 3 H₂ (g)

Isotopes[link]

Natural holmium contains one stable isotope, holmium-165. Some synthetic radioactive isotopes are known; the most stable one is holmium-163, with a half life of 4570 years. All other radioisotopes have ground-state half lives not greater than 1.117 days, and most have half lives under 3 hours. However, the metastable ^166m1Ho has a half life of around 1200 years because of its high spin. This fact, combined with a high excitation energy resulting in a particularly rich spectrum of decay gamma rays produced when the metastable state de-excites, makes this isotope useful in nuclear physics experiments as a means for calibrating energy responses and intrinsic efficiencies of gamma ray spectrometers.

History[link]

Holmium (Holmia, Latin name for Stockholm) was discovered by Marc Delafontaine and Jacques-Louis Soret in 1878 who noticed the aberrant spectrographic absorption bands of the then-unknown element (they called it "Element X").^[5][6] Later in 1878, Per Teodor Cleve independently discovered the element while he was working on erbia earth (erbium oxide).^[7][8]

Using the method developed by Carl Gustaf Mosander, Cleve first removed all of the known contaminants from erbia. The result of that effort was two new materials, one brown and one green. He named the brown substance holmia (after the Latin name for Cleve's home town, Stockholm) and the green one thulia. Holmia was later found to be the holmium oxide and thulia was thulium oxide.^[9]

Occurrence and production[link]

Gadolinite

Like all other rare earths, holmium is not naturally found as a free element. It does occur combined with other elements in gadolinite, monazite, and other rare-earth minerals. The main mining areas are China, United States, Brazil, India, Sri Lanka, and Australia with reserves of holmium estimated as 400,000 tonnes.^[9]

It is commercially extracted via ion-exchange from monazite sand (0.05% holmium) but is still difficult to separate from other rare earths. The element has been isolated through the reduction of its anhydrous chloride or fluoride with metallic calcium.^[10] Its estimated abundance in the Earth's crust is 1.3 mg/kg. Holmium obeys the Oddo-Harkins rule: as an odd-numbered element, it is less abundant than its immediate even-numbered neighbors, dysprosium and erbium. However, it is the most abundant of the odd-numbered heavy lanthanides. The principal current source are some of the ion-adsorption clays of southern China. Some of these have a rare-earth composition similar to that found in xenotime or gadolinite. Yttrium makes up about two-thirds of the total by weight; holmium is around 1.5%. The original ores themselves are very lean, maybe only 0.1% total lanthanide, but are easily extracted.^[11] Holmium is relatively inexpensive for a rare-earth metal with the price about US$ 1000 per kg.^[12]

Applications[link]

A solution of 4% holmium oxide in 10% perchloric acid, permanently fused into a quartz cuvette as an optical calibration standard

Holmium has the highest magnetic strength of any element, and therefore is used to create the strongest artificially generated magnetic fields, when placed within high-strength magnets as a magnetic pole piece (also called a magnetic flux concentrator). Since it can absorb nuclear fission-bred neutrons, it is also used in nuclear control rods.^[9]

Holmium is used in yttrium-iron-garnet (YIG)- and yttrium-lanthanum-fluoride (YLF) solid-state lasers found in microwave equipment (which are in turn found in a variety of medical and dental settings). Holmium lasers emit at 2.08 micrometres, and therefore are safe to eyes. They are used in medical, dental, and fiber-optical applications.^[2]

Holmium is one of the colorants used for cubic zirconia and glass, providing yellow or red coloring.^[13] Glass containing holmium oxide and holmium oxide solutions (usually in perchloric acid) have sharp optical absorption peaks in the spectral range 200–900 nm. They are therefore used as a calibration standard for optical spectrophotometers,^[14] and are available commercially.^[15]

The radioactive but long-lived Ho-166m1 (see "Isotopes" above) is used in calibration of gamma ray spectrometers.^[16]

Precautions[link]

The element, as with other rare earths, appears to have a low degree of acute toxicity. Holmium plays no biological role in humans, but may be able to stimulate metabolism.^[10]

See also[link]

• Holmium compounds

References[link]

• Guide to the Elements – Revised Edition, Albert Stwertka, (Oxford University Press; 1998) ISBN 0-19-508083-1

External links[link]

Wikimedia Commons has media related to: Holmium

Look up holmium in Wiktionary, the free dictionary.

• WebElements.com – Holmium (also used as a reference)
• American Elements – Holmium (also used as a reference)

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Richard "Wolfie" Wolf is a multi-platinum-selling music producer, songwriter and remixer, and an Emmy Award winning film and television composer.^[1]

Wolf got his start writing songs for his band and various artists before working for Warner/Chappell Music as staff songwriter. Soon after, he wrote and produced music for several feature films. He wrote the theme song for the Rodney Dangerfield film, Back To School^{[2] [3]} and began contribute to many large film projects, most notably producing for Southside Johnny & The Asbury Jukes for the number one box office Karate Kid II^[4] and penning a song for the Madonna (entertainer) vehicle, Who's That Girl.^[5] In 1989 he teamed up with Brett "Epic" Mazur to form the production team Wolf & Epic. Wolf & Epic were among the first record makers to break down the barriers between R&B, Hip-hop & Pop at the beginning of the 1990s. During this time, Wolf worked on projects for artists such as MC Lyte^[6], Prince , Seal ^[7], New Kids on the Block , Nona Gaye^[8], Coolio^[9], New Edition^[10], Sheena Easton, Laquan and Bell Biv Devoe. Bell Biv Devoe's debut album Poison and remix album WBBD-Bootcity both featured Wolf's production, and were certified triple Platinum and Gold respectively. Acid Jazz was another new fusion of musical styles which Wolf & Epic helped pioneer with their work on the first Acid Jazz compilation The Rebirth of the Cool Vol.1 (Island Records).

In the 21st Century Wolf's focus turned back to producing and composing for visual media. His score for the Warner Bros. cartoon Static Shock shook up Saturday morning programming with its fusion of hip-hop, electronic and traditional score, for which it was recognized with two Daytime Emmy nominations in 2003 and 2004 and one win ^{[11] [12] [13] [14]} . His work continues to regularly appear in film and television, including NCIS and NCIS: Los Angeles, and the longest running show on the CW, America's Next Top Model ^[15] . Wolf is also one of the busiest composers in the specialized arena of music for Televised sports, namely Fox Sports (United States)^[16]. He also currently works with a diversity of charities and is a board member of the I Have A Dream Foundation.

Musician[link]

Wolf, a Manhattan native, signed his first record deal, with Quinn Ivy Studios in Muscle Shoals, Alabama, while still a freshman at George Washington University. It was at those sessions that he met legendary Muscle Shoals guitar player Wayne Perkins, with whom he later co-wrote songs for the funky Southern rock band Crimson Tide. The group released two albums for Capitol Records in 1978 and 1979, which enjoyed limited success. Wolf then signed as a staff songwriter with Warner/Chappell Music. While there, he worked on various film and television projects, and artists including Steve Cropper, Angela Bofill, Johnny Gill and Toni Basil covered his songs.

Record Producer & Songwriter[link]

In 1989 Wolf teamed up with his former studio intern Brett "Epic" Mazur to form what major west coast artist manager Jerry Heller (of N.W.A and Eazy-E) would describe as "the hottest producing team of the early 1990s:"^[17] Wolf & Epic (initially named Peace Productions). Wolf's vision was to record live the type of funk and R&B that was commonly sampled by hip hop producers and then overlay scratching and other hip hop techniques to give it a new dimension. Wolf played guitar and keyboards, Mazur played drums and deejayed, and other musicians were brought in to fatten the sound. Mazur praised his older counterpart as having "the knack to come up with that undeniable hook. Even if it's just a keyboard part, he goes beyond just a chorus". ^[18]

The two musicians used the generation gap to their advantage and were able to span several genres and styles in their acclaimed productions.

Wolf & Epic's first project together was with Laquan on his album Notes of a Native Son. This record was one of the first to combine a live band with hip hop scratching, sampling, and rapping.^[19] The New York Times praised Laquan, saying that listening to his music is "to hear the shape of urban debates to come" and admired the "slick pop choruses [that] buoy his songs".^[20] One of the tracks was included on the compilation The Rebirth of the Cool Vol. 1 (Island Records), which spawned a string of albums that pioneered the "Acid Jazz" movement of jazzy hip hop. The duo later wrote and recorded another acid jazz hit, "Eyes of the Soul," on MC Lyte's Atlantic Records album Act Like You Know.

In the early 1990s, Wolf & Epic, along with other producers, worked on Bell Biv Devoe's album, Poison: a triple-platinum album that pioneered the fusion of soul and hip hop. Wolf & Epic, who had a #1 hit with their remixed version of Bell Biv Devoe's "Do Me",^[21] went on to "use the finished record as raw material... [to] completely re-produce it".^[22] The result was WBBD-Bootcity!: The Remix Album, the chart topping, certified gold album of Bell Biv Devoe remixes that sealed Wolf & Epic's reputation as "the hot new kids on the remixing block".^[22]

Some of Wolf's other notable projects during this time include work on Ralph Tresvant's "Public Figure," Sheena Easton's "You Can Swing It", remixes of Prince's "Horny Pony" and Seal's "Crazy", and work with the New Kids on the Block and Nona Gaye.

After Wolf and Mazur amicably parted ways, Wolf continued to write, produce, and remix records with artists including Freddie Mercury, Coolio^[23] , Ce Ce Peniston ("I Will Be Received"), MC Lyte, Ricky Bell, and Johnny Gill.

Film Music Production & Composition[link]

Wolf broke into the film industry when he co-wrote and produced several songs (including the title song) for Rodney Dangerfield's film, Back to School, in 1985^[24] . After that project, Wolf wrote and produced music for several more major film projects including The Karate Kid, Part II^[25] and Madonna's Who's That Girl^[26] . Wolf's work on Scooby-Doo and the Cyber Chase marked his entry into composing for animated stories. The filmmakers wanted to move Scooby Doo into the new century, which Wolf fully embraced.^[27] Wolf's other film credits include Strictly Business, starring Halle Berry and debuting Mary J. Blige; Three Kings^[28], where Wolf worked with director David O. Russell and actor Mark Wahlberg; and the Harrison Ford drama Presumed Innocent.

Emmy Award Winning Television Music Production & Composition[link]

Over the span of nearly two decades, Wolf's musical creations have been featured in thousands of TV episodes including top rated shows such NCIS, NCIS: Los Angeles, The Good Wife, ER, The X-Files, Fox Sports and ABC News' 20/20.

Wolf's introduction to branding music for TV came when Fox asked him to write original music for its Health Net cable. Then in 1999, he was asked to write original themes and identification music for the Fox Sports Network. The Hollywood Reporter explained, "it's his job to come up with two-minutes pieces of music that are flexible enough to work with sports as diverse as golf and beach volleyball, and distinctive enough to work as a branding device for the network".^[29] Since 1999, Fox has used Wolf's themes for almost two dozen network sports programs. The wide variety of Fox Sports themes & underscore cues that Wolf has composed have been played on thousands of sports broadcasts ranging from Major League Baseball, NASCAR and NFL to women's volleyball and golf.^[27]

Wolf's animation experience from Scooby-Doo and the Cyber Chase project led to his job composing for the Warner Bros. top rated Saturday morning show Static Shock — a project that would earn him various awards. "The beauty of doing a show like this is that you can draw on a broad spectrum of styles," Wolf says, "Superhero animation tends to be music-driven, and it can be a virtual playground for composers... The breadth of creative self-expression is truly liberating, especially after coming from the field of record production, where you're invariably pigeonholed into a single genre".^[30] The score combined hip-hop and electronica with a traditional orchestration and brought an edgy urban soundtrack to Saturday morning cartoons. The National Academy of Television Arts and Sciences recognized the originality of the score by awarding Wolf Daytime Emmy nominations two years in a row and an Emmy Award for Outstanding Music Composition and Direction and won in 2004.

Another one of Wolf's impressive television credits comes from Tyra Banks' hit television series, America's Next Top Model. For over fourteen seasons the show has relied heavily on Wolf's original music for everything from hip-hop tunes to themes for judging and elimination sequences. In 2008, a special issue of The Hollywood Reporter honored the 100th episode of ANTM and cited Wolf's musical contributions, explaining how the "music elevates the drama among competitors".^[31]

Working from his boutique music production and publishing company, The Producers Lab, Inc., Wolf continues to write and produce music for long time projects such as NCIS, Fox Sports, ABC News, and ANTM as well as a variety of others.

References[link]

External links[link]

• Official website

Dinesh Patel (born May 8, 1989 in Lucknow, India) is a right-handed baseball pitcher that played in the Pittsburgh Pirates organization. Along with Rinku Singh, he is the first Indian national ever to sign a contract with a major American sports club. Both Patel and Singh, had never thrown a baseball before besting over 37,000 competitors in The Million Dollar Arm, an Indian reality television show designed to find new baseball talent.^[1]

Patel, along with Singh, played for the Pirates' Gulf Coast League team.^[2] He had a successful, if brief, 2009 season for the Pirates, picking up a victory on August 13 (exactly one month after his countryman Singh got his first, and only, win of the year) and finishing with a 1-0 record and 1.42 ERA, allowing two runs (one earned) on six hits in 6.1 innings.^[3] Patel's 2010 season was less successful, withan 8.59 ERA in 7 1/3 innings, over nine games; he was released in December 2010.^[4]

External links[link]

• Career statistics and player information from Baseball-Reference (Minors)
• Million-Dollar Arm blog

References[link]