Chiral Systems Enantiomers and Enantioselective Surfaces

Introduction Life and Handedness Enantioselective Surfaces Theoretical point of view: selection of chiral molecules

Chiral systems Enantiomers and Enantioselective Surfaces

Leonardo Andrés Espinosa Leal1,2

1Nano-bio Spectroscopy Group. European Theoretical Spectroscopy Facility (ETSF) nanoquanta. Network of Excellence.

2Departamento de Física de Materiales, Facultad de Ciencias Químicas, Universidad del País Vasco, Centro Mixto UPV-CSIC.

January of 2008

Leonardo A. Espinosa L. Quiral systems Introduction What is Chirality? Life and Handedness A Chirality Timeline Enantioselective Surfaces classiﬁcation of chirality Theoretical point of view: selection of chiral molecules Enantiomers Outline

1 Introduction What is Chirality? A Chirality Timeline classiﬁcation of chirality Enantiomers

2 Life and Handedness Homochirality and life Some possibles answers

3 Enantioselective Surfaces Chiral surfaces

4 Theoretical point of view: selection of chiral molecules Selection methods

“Imagine. . . a musty storeroom crammed full of mannequin parts, left and right arms in rigidiﬁed plastic disarray And you, in the dark, have to sort them out. It’s a left-over Fellini set It’s soon done, but why is there one more right hand than left?”

Catalista, Selected Poems, 2002. Roald Hoffmann (Nobel prize in Chemistry,1981).

Deﬁnition: From Greek kheir:hand

“I call any geometrical ﬁgure or group of points, chiral, and say that its chirality, if its image in a plane mirror, ideally realized, cannot be brought to coincide with itself”a.

a W. Thomson Kelvin, Baltimore Lectures on Molecular Dynamics and the wave theory of light, C.J. Clay, London, 1904.

Catalista, Selected Poems, 2002. Roald Hoffmann (Nobel prize in Chemistry,1981).

Deﬁnition: From Greek kheir:hand

“I call any geometrical ﬁgure or group of points, chiral, and say that its chirality, if its image in a plane mirror, ideally realized, cannot be brought to coincide with itself”a.

a W. Thomson Kelvin, Baltimore Lectures on Molecular Dynamics and the wave theory of light, C.J. Clay, London, 1904.

Catalista, Selected Poems, 2002. Roald Hoffmann (Nobel prize in Chemistry,1981).

Deﬁnition: From Greek kheir:hand

“I call any geometrical ﬁgure or group of points, chiral, and say that its chirality, if its image in a plane mirror, ideally realized, cannot be brought to coincide with itself”a.

a W. Thomson Kelvin, Baltimore Lectures on Molecular Dynamics and the wave theory of light, C.J. Clay, London, 1904.

Catalista, Selected Poems, 2002. Roald Hoffmann (Nobel prize in Chemistry,1981).

Deﬁnition: From Greek kheir:hand

“I call any geometrical ﬁgure or group of points, chiral, and say that its chirality, if its image in a plane mirror, ideally realized, cannot be brought to coincide with itself”a.

a W. Thomson Kelvin, Baltimore Lectures on Molecular Dynamics and the wave theory of light, C.J. Clay, London, 1904.

Catalista, Selected Poems, 2002. Roald Hoffmann (Nobel prize in Chemistry,1981).

Deﬁnition: From Greek kheir:hand

“I call any geometrical ﬁgure or group of points, chiral, and say that its chirality, if its image in a plane mirror, ideally realized, cannot be brought to coincide with itself”a.

a W. Thomson Kelvin, Baltimore Lectures on Molecular Dynamics and the wave theory of light, C.J. Clay, London, 1904.

Catalista, Selected Poems, 2002. Roald Hoffmann (Nobel prize in Chemistry,1981).

Deﬁnition: From Greek kheir:hand

“I call any geometrical ﬁgure or group of points, chiral, and say that its chirality, if its image in a plane mirror, ideally realized, cannot be brought to coincide with itself”a.

a W. Thomson Kelvin, Baltimore Lectures on Molecular Dynamics and the wave theory of light, C.J. Clay, London, 1904.

1 Introduction What is Chirality? A Chirality Timeline classiﬁcation of chirality Enantiomers

2 Life and Handedness Homochirality and life Some possibles answers

3 Enantioselective Surfaces Chiral surfaces

4 Theoretical point of view: selection of chiral molecules Selection methods

History Path until XIX century

1 250B.C. Archimedes of Syracuse. The design of the Archimedean water screw and the study of spiral structure. 2 1811. Dominique FranÃ§ois Jean Arago. Discovery of the rotation of the polarization of light in quartz crystals. 3 1835. Jean-Baptiste Biot. Discovery of the rotation of the polarization of light in sugar solution. 4 1848. Louis Pasteur. Paratartaric acid is identiﬁed as the stereoisomer of tartaric acid. Pasteur postulates that nature has a chiral asymmetry. 5 1888. Friedrich Reinitzer. Discovery of the (chiral) blue phase of liquid crystals. Coining of the term "liquid crystals". 6 1893. William Thomson (Lord Kelvin). Deﬁnes the notion of a chiral object and chirality.

History Path until XIX century

History Path after XIX century

1 1951. Linus Pauling and Robert Brainard Corey. Discovery of the alpha-helix in protein. 2 1953. James D. Watson and Francis Crick. Discovery of the DNA double-helix. 3 1956. Tsung Dao Lee and Chen Ning Yang. Proposal of parity nonconservation to explain the "theta-tau" paradox. 4 1957. Chien-Shiung Wu. Discovery of parity violation in the beta-decay of 60Co. 5 1958. Richard P. Feynman, Murray Gell-Mann, Robert E. Marshak and E.C. George Sudarshan. Parity violating "vector–axial vector" theory of the weak interaction. 6 1964. James Cronin and Val L. Fitch. Discovery of CP violation in neutral kaon decays. 7 1973. Howard C. Berg and Robert A. Anderson. Prediction and conﬁrmation of rotary motion in bacterial ﬂagella.

History Path after XIX century

1 Introduction What is Chirality? A Chirality Timeline classiﬁcation of chirality Enantiomers

2 Life and Handedness Homochirality and life Some possibles answers

3 Enantioselective Surfaces Chiral surfaces

4 Theoretical point of view: selection of chiral molecules Selection methods

Isomers: molecules with the same chemical formula and often with the same kinds of chemical bonds between atoms, but in which the atoms are arranged differently. The atoms and functional groups are joined together in different ways. The bond structure is the same, but the geometrical positioning of atoms and functional groups in space differs. Enantiomers where different isomers are non-superimposable mirror-images of each other, and diastereomers when they are not.

1 Introduction What is Chirality? A Chirality Timeline classiﬁcation of chirality Enantiomers

2 Life and Handedness Homochirality and life Some possibles answers

3 Enantioselective Surfaces Chiral surfaces

4 Theoretical point of view: selection of chiral molecules Selection methods

“How would you like to live in a looking-glass house, Kitty? ... Perhaps looking-glass milk isn’t good to drink.” Alice to her cat. Through the Looking-Glass and What Alice Found There. Lewis Carroll, 1871.

1 (R)-limonene smells of oranges while its enantiomer, (S)-limonene, smells of lemons. 2 From 1956 to 1962, approximately 10,000 children were born with severe malformities, including phocomelia, because their mothers had taken thalidomide during pregnancy.

Leonardo A. Espinosa L. Quiral systems Introduction Life and Handedness Homochirality and life Enantioselective Surfaces Some possibles answers Theoretical point of view: selection of chiral molecules Outline

1 Introduction What is Chirality? A Chirality Timeline classiﬁcation of chirality Enantiomers

2 Life and Handedness Homochirality and life Some possibles answers

3 Enantioselective Surfaces Chiral surfaces

4 Theoretical point of view: selection of chiral molecules Selection methods

Chirality as a Problem in Underestanding the Origin of Life

Chirality is intrinsic to complex molecules. What was surprising was that all life uses L-Amino Acids (read proteins) and D-Sugars (DNA and RNA) Huge implications for origins of life.

First Big Question

Does life require homochirality to initiate or does life produce homochirality?

Preliminary answers

1 Life seems to require homochirality.

2 Must be a mechanism that either Naturally selects for a certain chirality. Produces a homochiral solution.

Chirality as a Problem in Underestanding the Origin of Life

Chirality is intrinsic to complex molecules. What was surprising was that all life uses L-Amino Acids (read proteins) and D-Sugars (DNA and RNA) Huge implications for origins of life.

First Big Question

Does life require homochirality to initiate or does life produce homochirality?

Preliminary answers

1 Life seems to require homochirality.

2 Must be a mechanism that either Naturally selects for a certain chirality. Produces a homochiral solution.

Chirality as a Problem in Underestanding the Origin of Life

Chirality is intrinsic to complex molecules. What was surprising was that all life uses L-Amino Acids (read proteins) and D-Sugars (DNA and RNA) Huge implications for origins of life.

First Big Question

Does life require homochirality to initiate or does life produce homochirality?

Preliminary answers

1 Life seems to require homochirality.

2 Must be a mechanism that either Naturally selects for a certain chirality. Produces a homochiral solution.

Chirality as a Problem in Underestanding the Origin of Life

Chirality is intrinsic to complex molecules. What was surprising was that all life uses L-Amino Acids (read proteins) and D-Sugars (DNA and RNA) Huge implications for origins of life.

First Big Question

Does life require homochirality to initiate or does life produce homochirality?

Preliminary answers

1 Life seems to require homochirality.

2 Must be a mechanism that either Naturally selects for a certain chirality. Produces a homochiral solution.

Chirality as a Problem in Underestanding the Origin of Life

Chirality is intrinsic to complex molecules. What was surprising was that all life uses L-Amino Acids (read proteins) and D-Sugars (DNA and RNA) Huge implications for origins of life.

First Big Question

Does life require homochirality to initiate or does life produce homochirality?

Preliminary answers

1 Life seems to require homochirality.

2 Must be a mechanism that either Naturally selects for a certain chirality. Produces a homochiral solution.

Chirality as a Problem in Underestanding the Origin of Life

Chirality is intrinsic to complex molecules. What was surprising was that all life uses L-Amino Acids (read proteins) and D-Sugars (DNA and RNA) Huge implications for origins of life.

First Big Question

Does life require homochirality to initiate or does life produce homochirality?

Preliminary answers

1 Life seems to require homochirality.

2 Must be a mechanism that either Naturally selects for a certain chirality. Produces a homochiral solution.

Chirality as a Problem in Underestanding the Origin of Life

Chirality is intrinsic to complex molecules. What was surprising was that all life uses L-Amino Acids (read proteins) and D-Sugars (DNA and RNA) Huge implications for origins of life.

First Big Question

Does life require homochirality to initiate or does life produce homochirality?

Preliminary answers

1 Life seems to require homochirality.

2 Must be a mechanism that either Naturally selects for a certain chirality. Produces a homochiral solution.

Chirality as a Problem in Underestanding the Origin of Life

Chirality is intrinsic to complex molecules. What was surprising was that all life uses L-Amino Acids (read proteins) and D-Sugars (DNA and RNA) Huge implications for origins of life.

First Big Question

Does life require homochirality to initiate or does life produce homochirality?

Preliminary answers

1 Life seems to require homochirality.

2 Must be a mechanism that either Naturally selects for a certain chirality. Produces a homochiral solution.

1 Introduction What is Chirality? A Chirality Timeline classiﬁcation of chirality Enantiomers

2 Life and Handedness Homochirality and life Some possibles answers

3 Enantioselective Surfaces Chiral surfaces

4 Theoretical point of view: selection of chiral molecules Selection methods

Answer 1 Anothers answers God: Intelligent design. (unsatisfactory, until now)

Parity. Weak nuclear interaction. Answer 2 Two Chirally Selective Sources. The truth is out here: Panspermia Circularly polarized light (CPL). or Exogenesis. Location of galaxy. Meteoritic Evidence. Answer 3 Magnetochiral dichroism. Mixture of both.

Answer 1 Anothers answers God: Intelligent design. (unsatisfactory, until now)

Leonardo A. Espinosa L. Quiral systems Introduction Life and Handedness Chiral surfaces Enantioselective Surfaces Theoretical point of view: selection of chiral molecules Outline

1 Introduction What is Chirality? A Chirality Timeline classiﬁcation of chirality Enantiomers

2 Life and Handedness Homochirality and life Some possibles answers

3 Enantioselective Surfaces Chiral surfaces

4 Theoretical point of view: selection of chiral molecules Selection methods

Leonardo A. Espinosa L. Quiral systems Introduction Life and Handedness Chiral surfaces Enantioselective Surfaces Theoretical point of view: selection of chiral molecules

Creation of chiral surfaces

Growth of chiral solid ﬁlms. Clean metal chiral surfaces. Organic chiral adsorbates modiﬁed metal surfaces. Adsorbate induced chiral facets.

Physical study of chiral surfaces